From 7276ae3d6ef4f119d1ce558ef0f3351e5e4dc004 Mon Sep 17 00:00:00 2001
From: DeviceInfra <no-reply@google.com>
Date: Thu, 7 May 2026 02:57:16 -0700
Subject: [PATCH] Internal change

PiperOrigin-RevId: 911851595
---
 .../v6/angular/app/core/models/host_action.ts | 107 ++-
 .../services/config/fake_config_service.ts    |   7 +-
 .../core/services/host/fake_host_service.ts   | 104 +--
 .../app/core/services/host/host_service.ts    |  20 +-
 .../services/host/http_host_service.spec.ts   |  27 +-
 .../core/services/host/http_host_service.ts   |  23 +-
 .../services/mock_data/hosts/01_no_config.ts  |   3 +
 .../mock_data/hosts/02_basic_editable.ts      |   2 +
 .../hosts/04_pusher_properties_only.ts        |   3 +
 .../mock_data/hosts/12_no_valid_versions.ts   |  21 +
 .../mock_data/hosts/multi_remote_control.ts   |   9 +-
 .../services/mock_data/hosts/overview_13.ts   |   5 +
 .../services/mock_data/hosts/overview_14.ts   |  20 +
 .../hosts/remote_control_permissions.ts       |  11 +-
 .../mock_data/hosts/ui_status_utils.ts        | 316 ++++++++-
 .../app/core/services/mock_data/index.ts      |   2 +
 .../app/core/services/mock_data/models.ts     |   6 +-
 .../action_no_permission_content.ng.html      |   4 +
 .../action_no_permission_content.scss         |  19 +
 .../action_no_permission_content.spec.ts      |  51 ++
 .../action_no_permission_content.ts           |  31 +
 .../flags_dialog/flags_dialog.ng.html         | 178 +++++
 .../flags_dialog/flags_dialog.scss            | 575 ++++++++++++++++
 .../flags_dialog/flags_dialog.ts              | 251 +++++++
 .../host_overview/host_overview.ng.html       |  59 +-
 .../components/host_overview/host_overview.ts | 141 +++-
 .../no_valid_versions_content.ng.html         |   4 +
 .../no_valid_versions_content.scss            |  19 +
 .../no_valid_versions_content.spec.ts         |  33 +
 .../no_valid_versions_content.ts              |  17 +
 .../release_dialog/release_dialog.ng.html     | 310 +++++++++
 .../release_dialog/release_dialog.scss        | 612 ++++++++++++++++++
 .../release_dialog/release_dialog.ts          | 156 +++++
 .../config_common/dialog/dialog.ng.html       |   5 +-
 .../components/config_common/dialog/dialog.ts |   1 +
 .../confirm_dialog/confirm_dialog.ng.html     |   4 +-
 .../confirm_dialog/confirm_dialog.scss        |   4 +-
 .../confirm_dialog/confirm_dialog.ts          |  17 +-
 .../service/proto/host/host_resources.proto   |  55 +-
 .../v6/service/proto/host/host_service.proto  |  27 +-
 .../v6/service/host/HostServiceGrpcImpl.java  |  14 +-
 .../fe/v6/service/host/HostServiceLogic.java  |   7 +-
 .../v6/service/host/HostServiceLogicImpl.java |  40 +-
 .../service/host/{builder => builders}/BUILD  |   5 +-
 .../builders/NoOpPopularFlagsBuilder.java     |  36 ++
 .../NoOpRemoteControlUrlBuilder.java          |   2 +-
 .../host/builders/PopularFlagsBuilder.java    |  30 +
 .../RemoteControlUrlBuilder.java              |   2 +-
 .../fe/v6/service/host/handlers/BUILD         |   2 +-
 .../host/handlers/GetPopularFlagsHandler.java |  42 ++
 .../handlers/NoOpPopularFlagsBuilder.java     |  15 +
 ...PreflightLabServerReleaseActionHelper.java |  44 ++
 ...PreflightLabServerReleaseActionHelper.java |  30 +
 .../PreflightLabServerReleaseHandler.java     |  44 ++
 .../handlers/RemoteControlDevicesHandler.java |   2 +-
 .../mobileharness/fe/v6/service/shared/BUILD  |   3 +-
 .../fe/v6/service/shared/OssStubsModule.java  |  14 +-
 .../fe/v6/service/util/FeatureReadiness.java  |   2 +-
 .../mobileharness/fe/v6/service/host/BUILD    |   3 +-
 .../host/HostServiceLogicImplTest.java        |  53 +-
 .../fe/v6/service/host/handlers/BUILD         |   2 +-
 .../PreflightLabServerReleaseHandlerTest.java |  80 +++
 .../RemoteControlDevicesHandlerTest.java      |   2 +-
 .../v6/service/util/FeatureReadinessTest.java |   5 +
 64 files changed, 3509 insertions(+), 229 deletions(-)
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/12_no_valid_versions.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ng.html
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.scss
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.spec.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ng.html
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.scss
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ng.html
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.scss
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.spec.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ts
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ng.html
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.scss
 create mode 100644 src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ts
 rename src/java/com/google/devtools/mobileharness/fe/v6/service/host/{builder => builders}/BUILD (85%)
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpPopularFlagsBuilder.java
 rename src/java/com/google/devtools/mobileharness/fe/v6/service/host/{builder => builders}/NoOpRemoteControlUrlBuilder.java (99%)
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/PopularFlagsBuilder.java
 rename src/java/com/google/devtools/mobileharness/fe/v6/service/host/{builder => builders}/RemoteControlUrlBuilder.java (99%)
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/GetPopularFlagsHandler.java
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPopularFlagsBuilder.java
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPreflightLabServerReleaseActionHelper.java
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseActionHelper.java
 create mode 100644 src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandler.java
 create mode 100644 src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandlerTest.java

diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/models/host_action.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/models/host_action.ts
index 3ca6231613..ec306c2f28 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/models/host_action.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/models/host_action.ts
@@ -55,23 +55,47 @@ export declare interface PopularFlag {
 }
 
 /**
- * A preset configuration for pass-through flags.
+ * Response for GetPopularFlags API.
  */
-export declare interface FlagPreset {
-  readonly label: string;
-  readonly value: string;
-  readonly description: string;
+export declare interface GetPopularFlagsResponse {
+  readonly flags: PopularFlag[];
 }
 
+/**
+ * Response for PreflightLabServerRelease API.
+ */
+export declare interface PreflightLabServerReleaseResponse {
+  readonly permissionDenied?: PermissionDenied;
+  readonly ready?: ReleaseReady;
+}
+
+/**
+ * No deploy permission.
+ */
+export declare interface PermissionDenied {}
+
+/**
+ * All checks passed. Here are the available versions to deploy.
+ */
+export declare interface ReleaseReady {
+  readonly versions: DeployableVersion[];
+}
+
+/**
+ * Represents the status of a Lab Server release.
+ */
+export type ReleaseStatus = 'Latest' | 'Current' | 'Deprecated' | '';
+
 /**
  * Configuration for a specific Lab Server release.
  */
-export declare interface HostReleaseConfig {
+export declare interface DeployableVersion {
   readonly name: string;
   readonly version: string;
-  readonly port: ReleasePort;
-  readonly syncCMD: string[];
-  readonly asyncCMD: string[];
+  readonly status: ReleaseStatus;
+  readonly buildTime: string;
+  readonly ports?: ReleasePort[];
+  readonly releaseDetails?: ReleaseDetails;
 }
 
 /**
@@ -82,11 +106,76 @@ export declare interface ReleasePort {
   readonly portNumber: number;
 }
 
+/**
+ * Details about a specific release.
+ */
+export declare interface ReleaseDetails {
+  readonly changeLogs?: ChangeLogGroup[];
+  readonly files?: FileRecord[];
+  readonly syncCommands?: CommandRecord[];
+  readonly asyncCommands?: CommandRecord[];
+}
+
+/**
+ * Represents a group of changes or bugs related to a release.
+ */
+export declare interface ChangeLogGroup {
+  readonly name: string;
+  readonly items: ChangeLogItem[];
+}
+
+/**
+ * Represents a single change record or bug record for a release.
+ */
+export declare interface ChangeLogItem {
+  readonly change?: ChangeRecord;
+  readonly bug?: BugRecord;
+}
+
+/**
+ * Represents a single change record for a release.
+ */
+export declare interface ChangeRecord {
+  readonly cl: number;
+  readonly author: string;
+  readonly text: string;
+  readonly bugs: number[];
+}
+
+/**
+ * Represents a single bug record for a release.
+ */
+export declare interface BugRecord {
+  readonly bug: number;
+  readonly text: string;
+}
+
+/**
+ * Represents a single file record for a release.
+ */
+export declare interface FileRecord {
+  readonly name: string;
+  readonly path: string;
+}
+
+/**
+ * Represents a single command record for a release.
+ */
+export declare interface CommandRecord {
+  readonly name: string;
+  readonly command: string;
+}
+
 /**
  * Response for DecommissionHost API.
  */
 export declare interface DecommissionHostResponse {}
 
+/**
+ * Response for UpdatePassThroughFlags API.
+ */
+export declare interface UpdatePassThroughFlagsResponse {}
+
 /**
  * Response for those rollout action
  */
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/config/fake_config_service.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/config/fake_config_service.ts
index 6bd5cadc5e..cd872be708 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/config/fake_config_service.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/config/fake_config_service.ts
@@ -63,7 +63,12 @@ export class FakeConfigService extends ConfigService {
     const isHostManaged = scenario.overview.host.name === 'host-x.example.com';
     const hostName = scenario.overview.host.name;
 
-    let uiStatus: Partial<DeviceConfigUiStatus> | undefined;
+    let uiStatus: Partial<DeviceConfigUiStatus> | undefined = {
+      permissions: {visible: true, editability: {editable: true}},
+      wifi: {visible: true, editability: {editable: true}},
+      dimensions: {visible: true, editability: {editable: true}},
+      settings: {visible: true, editability: {editable: true}},
+    };
     if (deviceId === 'WIFI_DIMENSIONS_ONLY_DEVICE') {
       uiStatus = {
         permissions: {visible: false},
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/fake_host_service.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/fake_host_service.ts
index bb274e53ca..2ba0d5dfb0 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/fake_host_service.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/fake_host_service.ts
@@ -4,14 +4,15 @@ import {Observable, of, throwError} from 'rxjs';
 import {
   DecommissionHostResponse,
   GetHostDebugInfoResponse,
+  GetPopularFlagsResponse,
   HostHeaderInfo,
-  HostReleaseConfig,
-  PopularFlag,
+  PreflightLabServerReleaseResponse,
   ReleaseLabServerRequest,
   ReleaseLabServerResponse,
   RestartLabServerResponse,
   StartLabServerResponse,
   StopLabServerResponse,
+  UpdatePassThroughFlagsResponse,
 } from '../../models/host_action';
 import {
   CheckRemoteControlEligibilityResponse,
@@ -25,7 +26,10 @@ import {
   RemoteControlDevicesResponse,
 } from '../../models/host_overview';
 import {MOCK_HOST_SCENARIOS} from '../mock_data';
-import {createHostActions} from '../mock_data/hosts/ui_status_utils';
+import {
+  createDefaultReleaseResponse,
+  createHostActions,
+} from '../mock_data/hosts/ui_status_utils';
 import {HostService} from './host_service';
 
 /**
@@ -110,34 +114,58 @@ export class FakeHostService extends HostService {
     });
   }
 
-  override getPopularFlags(hostName: string): Observable<PopularFlag[]> {
-    return of([
-      {
-        name: 'No Mute Android',
-        description: 'Disables muting of Android devices',
-        cmd: '--nomute_android',
-      },
-      {
-        name: 'No Binary Log',
-        description: 'Disables binary logging to save space',
-        cmd: '--nobinarylog',
-      },
-      {
-        name: 'Enable Linux Device',
-        description: 'Enables support for Linux devices',
-        cmd: '--enable_linux_device',
-      },
-    ]);
+  override getPopularFlags(
+    hostName: string,
+  ): Observable<GetPopularFlagsResponse> {
+    return of({
+      flags: [
+        {
+          name: 'Standard Satellite',
+          cmd: '--nomute_android --noandroid_device_daemon',
+          description: 'Default configuration for Android Satellite Labs',
+        },
+        {
+          name: 'Linux Support',
+          cmd: '--enable_linux_device',
+          description: 'Enables detection of Linux devices',
+        },
+        {
+          name: 'Debug Mode',
+          cmd: '--debug_mode=true --verbose',
+          description: 'Enables verbose logging for debugging',
+        },
+        {
+          name: 'Flashstation Cache',
+          cmd: '--flashstation_cache_dir=/tmp/fs_cache',
+          description: 'Custom cache directory for Flashstation',
+        },
+        {
+          name: 'No Binary Log',
+          cmd: '--nobinarylog',
+          description: 'Disables binary logging to save space',
+        },
+        {
+          name: 'Custom Flag',
+          cmd: `--my_message=":text: field_a: 'test' field_b: 123"`,
+          description: 'Custom flag for testing',
+        },
+        {
+          name: 'Custom Flag 2',
+          cmd: `--flagD="some value"`,
+          description: 'Custom flag for testing 2',
+        },
+      ],
+    });
   }
 
   override updatePassThroughFlags(
     hostName: string,
     flags: string,
-  ): Observable<void> {
+  ): Observable<UpdatePassThroughFlagsResponse> {
     const scenario = MOCK_HOST_SCENARIOS.find((s) => s.hostName === hostName);
     if (scenario && scenario.overview) {
       scenario.overview.labServer.passThroughFlags = flags;
-      return of(undefined);
+      return of({});
     } else {
       return throwError(
         () =>
@@ -148,31 +176,13 @@ export class FakeHostService extends HostService {
     }
   }
 
-  override getReleaseConfigs(
+  override preflightLabServerRelease(
     hostName: string,
-  ): Observable<HostReleaseConfig[]> {
-    return of([
-      {
-        name: 'MH_SATELLITE_LAB',
-        version: '4.349.0',
-        port: {protocol: 'grpc', portNumber: 9994},
-        syncCMD: [
-          'sudo systemctl stop mobileharness-lab',
-          'sudo /usr/bin/mh_lab_installer --version 4.349.0',
-        ],
-        asyncCMD: ['sudo systemctl start mobileharness-lab'],
-      },
-      {
-        name: 'MH_SATELLITE_LAB',
-        version: '4.348.0',
-        port: {protocol: 'grpc', portNumber: 9994},
-        syncCMD: [
-          'sudo systemctl stop mobileharness-lab',
-          'sudo /usr/bin/mh_lab_installer --version 4.348.0',
-        ],
-        asyncCMD: ['sudo systemctl start mobileharness-lab'],
-      },
-    ]);
+  ): Observable<PreflightLabServerReleaseResponse> {
+    const scenario = MOCK_HOST_SCENARIOS.find((s) => s.hostName === hostName);
+    const preflightLabServerReleaseResponse =
+      scenario?.releaseResponse || createDefaultReleaseResponse();
+    return of(preflightLabServerReleaseResponse);
   }
 
   override decommissionMissingDevices(
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/host_service.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/host_service.ts
index 961c2e94d9..5fff24553e 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/host_service.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/host_service.ts
@@ -1,16 +1,18 @@
 import {InjectionToken} from '@angular/core';
 import {Observable} from 'rxjs';
+
 import {
   DecommissionHostResponse,
-  ReleaseLabServerRequest,
-  ReleaseLabServerResponse,
   GetHostDebugInfoResponse,
+  GetPopularFlagsResponse,
   HostHeaderInfo,
-  HostReleaseConfig,
-  PopularFlag,
+  PreflightLabServerReleaseResponse,
+  ReleaseLabServerRequest,
+  ReleaseLabServerResponse,
   RestartLabServerResponse,
   StartLabServerResponse,
   StopLabServerResponse,
+  UpdatePassThroughFlagsResponse,
 } from '../../models/host_action';
 import {
   CheckRemoteControlEligibilityResponse,
@@ -57,7 +59,9 @@ export abstract class HostService {
   /**
    * Retrieves popular pass-through flags for a host.
    */
-  abstract getPopularFlags(hostName: string): Observable<PopularFlag[]>;
+  abstract getPopularFlags(
+    hostName: string,
+  ): Observable<GetPopularFlagsResponse>;
 
   /**
    * Updates the pass through flags for a specific host.
@@ -65,12 +69,14 @@ export abstract class HostService {
   abstract updatePassThroughFlags(
     hostName: string,
     flags: string,
-  ): Observable<void>;
+  ): Observable<UpdatePassThroughFlagsResponse>;
 
   /**
    * Retrieves release configurations for a host.
    */
-  abstract getReleaseConfigs(hostName: string): Observable<HostReleaseConfig[]>;
+  abstract preflightLabServerRelease(
+    hostName: string,
+  ): Observable<PreflightLabServerReleaseResponse>;
 
   /**
    * Decommissions missing devices on a specific host.
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.spec.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.spec.ts
index de0e31fd56..fd5d09732e 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.spec.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.spec.ts
@@ -8,10 +8,12 @@ import {TestBed} from '@angular/core/testing';
 import {APP_DATA, AppData} from '../../models/app_data';
 import {
   DecommissionHostResponse,
+  DeployableVersion,
   GetHostDebugInfoResponse,
+  GetPopularFlagsResponse,
   HostHeaderInfo,
-  HostReleaseConfig,
   PopularFlag,
+  PreflightLabServerReleaseResponse,
   ReleaseLabServerRequest,
   ReleaseLabServerResponse,
   RestartLabServerResponse,
@@ -133,14 +135,15 @@ describe('HttpHostService', () => {
 
   it('should retrieve popular flags', () => {
     const mockPopularFlags: PopularFlag[] = [{name: 'flag1'} as PopularFlag];
-    service.getPopularFlags('test-host').subscribe((flags) => {
-      expect(flags).toEqual(mockPopularFlags);
+    const mockResponse: GetPopularFlagsResponse = {flags: mockPopularFlags};
+    service.getPopularFlags('test-host').subscribe((response) => {
+      expect(response).toEqual(mockResponse);
     });
     const req = httpMock.expectOne(
       'http://testdomain.com/v6/hosts/test-host/popular-flags',
     );
     expect(req.request.method).toBe('GET');
-    req.flush(mockPopularFlags);
+    req.flush(mockResponse);
   });
 
   it('should update pass-through flags', () => {
@@ -154,17 +157,19 @@ describe('HttpHostService', () => {
   });
 
   it('should retrieve release configs', () => {
-    const mockConfigs: HostReleaseConfig[] = [
-      {name: 'config1'} as HostReleaseConfig,
-    ];
-    service.getReleaseConfigs('test-host').subscribe((configs) => {
-      expect(configs).toEqual(mockConfigs);
+    const mockResponse: PreflightLabServerReleaseResponse = {
+      ready: {
+        versions: [{name: 'config1'} as DeployableVersion],
+      },
+    };
+    service.preflightLabServerRelease('test-host').subscribe((response) => {
+      expect(response).toEqual(mockResponse);
     });
     const req = httpMock.expectOne(
-      'http://testdomain.com/v6/hosts/test-host/release-configs',
+      `http://testdomain.com/v6/hosts/test-host/preflightLabServerRelease`,
     );
     expect(req.request.method).toBe('GET');
-    req.flush(mockConfigs);
+    req.flush(mockResponse);
   });
 
   it('should decommission host', () => {
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.ts
index 75dbf00e14..1f4a6c5564 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/host/http_host_service.ts
@@ -8,14 +8,15 @@ import {APP_DATA, AppData} from '../../models/app_data';
 import {
   DecommissionHostResponse,
   GetHostDebugInfoResponse,
+  GetPopularFlagsResponse,
   HostHeaderInfo,
-  HostReleaseConfig,
-  PopularFlag,
+  PreflightLabServerReleaseResponse,
   ReleaseLabServerRequest,
   ReleaseLabServerResponse,
   RestartLabServerResponse,
   StartLabServerResponse,
   StopLabServerResponse,
+  UpdatePassThroughFlagsResponse,
 } from '../../models/host_action';
 import {
   CheckRemoteControlEligibilityResponse,
@@ -67,8 +68,10 @@ export class HttpHostService extends HostService {
     );
   }
 
-  override getPopularFlags(hostName: string): Observable<PopularFlag[]> {
-    return this.http.get<PopularFlag[]>(
+  override getPopularFlags(
+    hostName: string,
+  ): Observable<GetPopularFlagsResponse> {
+    return this.http.get<GetPopularFlagsResponse>(
       `${this.apiUrl}/${hostName}/popular-flags`,
     );
   }
@@ -76,8 +79,8 @@ export class HttpHostService extends HostService {
   override updatePassThroughFlags(
     hostName: string,
     flags: string,
-  ): Observable<void> {
-    return this.http.post<void>(
+  ): Observable<UpdatePassThroughFlagsResponse> {
+    return this.http.post<UpdatePassThroughFlagsResponse>(
       `${this.apiUrl}/${hostName}/updatePassThroughFlags`,
       {
         flags,
@@ -85,11 +88,11 @@ export class HttpHostService extends HostService {
     );
   }
 
-  override getReleaseConfigs(
+  override preflightLabServerRelease(
     hostName: string,
-  ): Observable<HostReleaseConfig[]> {
-    return this.http.get<HostReleaseConfig[]>(
-      `${this.apiUrl}/${hostName}/release-configs`,
+  ): Observable<PreflightLabServerReleaseResponse> {
+    return this.http.get<PreflightLabServerReleaseResponse>(
+      `${this.apiUrl}/${hostName}/preflightLabServerRelease`,
     );
   }
 
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/01_no_config.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/01_no_config.ts
index a207055e84..ba227a58e5 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/01_no_config.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/01_no_config.ts
@@ -18,4 +18,7 @@ export const SCENARIO_HOST_NO_CONFIG: MockHostScenario = {
   },
   defaultDeviceConfig: null,
   actions: createHostActions(),
+  releaseResponse: {
+    permissionDenied: {},
+  },
 };
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/02_basic_editable.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/02_basic_editable.ts
index cc612c2a85..4ff47ef106 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/02_basic_editable.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/02_basic_editable.ts
@@ -5,6 +5,7 @@ import {HostConfig} from '../../../models/host_config_models';
 import {MockHostScenario} from '../models';
 import {
   createDefaultHostOverview,
+  createDefaultReleaseResponse,
   createDefaultUiStatus,
   createHostActions,
 } from './ui_status_utils';
@@ -44,4 +45,5 @@ export const SCENARIO_HOST_BASIC_EDITABLE: MockHostScenario = {
   },
   defaultDeviceConfig: DEFAULT_DEVICE_CONFIG,
   actions: createHostActions(),
+  releaseResponse: createDefaultReleaseResponse(),
 };
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/04_pusher_properties_only.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/04_pusher_properties_only.ts
index 1b9cc87a57..71eba0a95b 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/04_pusher_properties_only.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/04_pusher_properties_only.ts
@@ -55,4 +55,7 @@ export const SCENARIO_HOST_PUSHER_PROPERTIES: MockHostScenario = {
   },
   defaultDeviceConfig: DEFAULT_DEVICE_CONFIG,
   actions: createHostActions(),
+  releaseResponse: {
+    permissionDenied: {},
+  },
 };
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/12_no_valid_versions.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/12_no_valid_versions.ts
new file mode 100644
index 0000000000..8e422bcdcb
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/12_no_valid_versions.ts
@@ -0,0 +1,21 @@
+/** @fileoverview Mock host scenario with no valid versions for release. */
+
+import {MockHostScenario} from '../models';
+import {SCENARIO_HOST_BASIC_EDITABLE} from './02_basic_editable';
+import {createDefaultHostOverview} from './ui_status_utils';
+
+/**
+ * Represents a mock host scenario where there are no valid versions for release.
+ */
+export const SCENARIO_HOST_NO_VALID_VERSIONS: MockHostScenario = {
+  ...SCENARIO_HOST_BASIC_EDITABLE,
+  hostName: 'no-valid-versions.host.example.com',
+  scenarioName: '12. No Valid Versions',
+  overview: createDefaultHostOverview('no-valid-versions.host.example.com'),
+  deviceSummaries: [],
+  releaseResponse: {
+    ready: {
+      versions: [],
+    },
+  },
+};
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/multi_remote_control.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/multi_remote_control.ts
index e983d3a08f..c3c8b77bee 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/multi_remote_control.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/multi_remote_control.ts
@@ -6,7 +6,11 @@ import {
   HostOverview,
 } from '../../../models/host_overview';
 import {MockHostScenario} from '../models';
-import {createDefaultUiStatus, createHostActions} from './ui_status_utils';
+import {
+  createDefaultUiStatus,
+  createDeviceActions,
+  createHostActions,
+} from './ui_status_utils';
 
 // Helper to create a basic HostOverview
 function createHostOverview(
@@ -278,6 +282,7 @@ const DEVICES_PROXY_MISMATCH: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 8',
     version: '14',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'RC-PROXY-MISMATCH-2',
@@ -292,6 +297,7 @@ const DEVICES_PROXY_MISMATCH: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 8 Pro',
     version: '21',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'RC-NO-PROXY',
@@ -302,6 +308,7 @@ const DEVICES_PROXY_MISMATCH: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 8 Pro',
     version: '21',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'RC-TESTBED-NO-PROXY',
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_13.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_13.ts
index 93adfa7333..7b3aa4995e 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_13.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_13.ts
@@ -4,6 +4,7 @@ import {MockHostScenario} from '../models';
 import {
   createDefaultHostOverview,
   createDefaultUiStatus,
+  createDeviceActions,
   createHostActions,
 } from './ui_status_utils';
 
@@ -55,6 +56,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:missing',
     model: 'Pixel 6',
     version: '13',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'MISSING-DEV-2',
@@ -69,6 +71,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:missing',
     model: 'Pixel 6 Pro',
     version: '13',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'MISSING-DEV-3',
@@ -83,6 +86,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:missing',
     model: 'Pixel 7',
     version: '14',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'ACTIVE-DEV-4',
@@ -97,6 +101,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:active',
     model: 'Pixel 8',
     version: '14',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
 ];
 
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_14.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_14.ts
index 8c182855ed..4491bbec18 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_14.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/overview_14.ts
@@ -4,6 +4,7 @@ import {MockHostScenario} from '../models';
 import {
   createDefaultHostOverview,
   createDefaultUiStatus,
+  createDeviceActions,
   createHostActions,
 } from './ui_status_utils';
 
@@ -122,6 +123,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2A311FDH300A2H',
@@ -156,6 +158,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2A311FDH300AAZ',
@@ -190,6 +193,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B011FDH300169',
@@ -224,6 +228,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B011FDH300FDY',
@@ -258,6 +263,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B011FDH300FFC',
@@ -292,6 +298,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH30015J',
@@ -326,6 +333,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH3007X2',
@@ -360,6 +368,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH300833',
@@ -394,6 +403,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH30087D',
@@ -428,6 +438,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH300891',
@@ -462,6 +473,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH3008EP',
@@ -496,6 +508,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH3008GN',
@@ -513,6 +526,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: '',
     version: '',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH3008GP',
@@ -547,6 +561,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: '2B021FDH3008MN',
@@ -581,6 +596,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: 'pixel 7 pro',
     version: '36',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'at1-ab7.atc.google.com:33487',
@@ -598,6 +614,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: '',
     version: '',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'at1-ab7.atc.google.com:35137',
@@ -615,6 +632,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: '',
     version: '',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'at1-ab7.atc.google.com:35555',
@@ -632,6 +650,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: '',
     version: '',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'at1-ab7.atc.google.com:36735',
@@ -649,6 +668,7 @@ const deviceSummaries: DeviceSummary[] = [
     requiredDims: 'pool:android-test-executor',
     model: '',
     version: '',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'at1-ab7.atc.google.com:38191',
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/remote_control_permissions.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/remote_control_permissions.ts
index 0e6f9485b5..ef3e78bb4c 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/remote_control_permissions.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/remote_control_permissions.ts
@@ -6,7 +6,11 @@ import {
   HostOverview,
 } from '../../../models/host_overview';
 import {MockHostScenario} from '../models';
-import {createDefaultUiStatus, createHostActions} from './ui_status_utils';
+import {
+  createDefaultUiStatus,
+  createDeviceActions,
+  createHostActions,
+} from './ui_status_utils';
 
 // Helper to create a basic HostOverview
 function createHostOverview(
@@ -58,6 +62,7 @@ const DEVICES_PERMISSIONS_ALL: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 8',
     version: '14',
+    actions: createDeviceActions('NO_PERMISSION'),
   },
   {
     id: 'RC-NO-PERM-2',
@@ -68,6 +73,7 @@ const DEVICES_PERMISSIONS_ALL: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 8 Pro',
     version: '14',
+    actions: createDeviceActions('NO_PERMISSION'),
   },
 
   // 2. Device with USER permission only
@@ -80,6 +86,7 @@ const DEVICES_PERMISSIONS_ALL: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 7',
     version: '13',
+    actions: createDeviceActions('USER_PERMISSION'),
   },
 
   // 3. Device with GROUP permission only
@@ -92,6 +99,7 @@ const DEVICES_PERMISSIONS_ALL: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 7 Pro',
     version: '13',
+    actions: createDeviceActions('GROUP_PERMISSION'),
   },
 
   // 4. Device with BOTH/ALL permissions
@@ -104,6 +112,7 @@ const DEVICES_PERMISSIONS_ALL: DeviceSummary[] = [
     requiredDims: '',
     model: 'Pixel 6',
     version: '12',
+    actions: createDeviceActions('ALL_PERMISSIONS'),
   },
   {
     id: 'RC-INVALID-ineligible-busy',
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/ui_status_utils.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/ui_status_utils.ts
index 644cd6b2e4..0d0189edcc 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/ui_status_utils.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/hosts/ui_status_utils.ts
@@ -2,7 +2,13 @@
  * @fileoverview Utility functions for creating UI status objects for mock data.
  */
 
-import {HostActions, LabServerActions} from '../../../models/host_action';
+import {DeviceActions} from '../../../models/device_action';
+import {
+  HostActions,
+  LabServerActions,
+  PreflightLabServerReleaseResponse,
+  ReleaseDetails,
+} from '../../../models/host_action';
 import {
   Editability,
   HostConfigUiStatus,
@@ -48,6 +54,251 @@ export function createPartStatus(
   };
 }
 
+function createDefaultReleaseDetails(): ReleaseDetails {
+  return {
+    changeLogs: [
+      {
+        name: 'Bug Fixes',
+        items: [
+          {
+            change: {
+              cl: 858423150,
+              author: 'test_author',
+              text: 'test_text',
+              bugs: [123456789],
+            },
+          },
+        ],
+      },
+    ],
+    syncCommands: [
+      {
+        name: 'test_sync_command',
+        command: 'test_command',
+      },
+    ],
+  };
+}
+
+/**
+ * Creates default release configs for mock scenarios.
+ */
+export function createDefaultReleaseResponse(): PreflightLabServerReleaseResponse {
+  return {
+    ready: {
+      versions: [
+        {
+          name: 'mobileharness_lab_server',
+          version: 'v4.349.0',
+          status: 'Latest',
+          buildTime: '2024-03-15 21:30:00',
+          ports: [{protocol: 'grpc', portNumber: 9994}],
+          releaseDetails: {
+            changeLogs: [
+              {
+                name: 'Bug Fixes',
+                items: [
+                  {
+                    change: {
+                      cl: 858423150,
+                      author: 'huiliu',
+                      text: 'Prevent lab-resolved files from being escaped in KickOffTestRequest.',
+                      bugs: [443716027, 468693971],
+                    },
+                  },
+                  {
+                    change: {
+                      cl: 858945464,
+                      author: 'huiliu',
+                      text: 'Resolve test files cannot be sent issue.',
+                      bugs: [468693971],
+                    },
+                  },
+                ],
+              },
+              {
+                name: 'Incremental Changes',
+                items: [
+                  {
+                    change: {
+                      cl: 858343140,
+                      author: 'huiliu',
+                      text: 'Support to set different master spec for different jobs in one session.',
+                      bugs: [476920060],
+                    },
+                  },
+                ],
+              },
+              {
+                name: 'Deprecated',
+                items: [
+                  {
+                    change: {
+                      cl: 858854515,
+                      author: 'zeek',
+                      text: 'Remove the logic to limit iOS simulator count based on disk type.',
+                      bugs: [473739492],
+                    },
+                  },
+                ],
+              },
+            ],
+            syncCommands: [
+              {
+                name: 'copy_tf_config',
+                command:
+                  'cp -f @android_tradefed_test_config /usr/local/google/mobileharness/android_tradefed_test_config_key',
+              },
+              {
+                name: 'copy_tf_credential',
+                command:
+                  'cp -f @android_tradefed_credential_key /usr/local/google/mobileharness/android_tradefed_test_key',
+              },
+              {
+                name: 'prepare_dual_home_lab_dir',
+                command:
+                  'mkdir -p /etc/dual_home_lab/agent && chmod -R 775 /etc/dual_home_lab/',
+              },
+              {
+                name: 'copy_credential',
+                command:
+                  'cp -f @udcluster_daemon_credential /etc/dual_home_lab/agent/dual-home-lab.json',
+              },
+              {
+                name: 'remove_mh_default_credential',
+                command:
+                  'rm -f /usr/local/google/mobileharness/mh_default_credential.json',
+              },
+              {
+                name: 'copy_robo_credential',
+                command:
+                  'cp -f @default_robo_credential /usr/local/google/mobileharness/default_robo_credential.json',
+              },
+              {
+                name: 'copy_file_transfer_credential',
+                command:
+                  'cp -f @file_transfer_credential /usr/local/google/mobileharness/file_transfer_credential.json',
+              },
+              {
+                name: 'copy_web_flashstation_key',
+                command:
+                  'cp -f @web_flashstation_key /usr/local/google/mobileharness/web_flashstation_key.json',
+              },
+              {
+                name: 'add_read_permission_of_credential',
+                command: 'chmod +r /etc/dual_home_lab/agent/dual-home-lab.json',
+              },
+              {
+                name: 'process_before_killing',
+                command: 'ps xao pid,ppid,pgid,command',
+              },
+              {
+                name: 'kill_zombie_lab_script',
+                command: '@legacy_daemon_killer',
+              },
+              {
+                name: 'process_after_killing',
+                command: 'ps xao pid,ppid,pgid,command',
+              },
+              {
+                name: 'clean_previous_lab_server',
+                command:
+                  '/usr/local/buildtools/java/jdk21/bin/java --uid= -loas_pwd_fallback_in_corp -jar @cleaner',
+              },
+            ],
+            asyncCommands: [
+              {
+                name: 'start_command_server',
+                command:
+                  '@command_server_binary --launcher_javabase=/usr/local/buildtools/java/jdk21 --uid= -loas_pwd_fallback_in_corp run',
+              },
+              {
+                name: 'start_mobileharness_lab_server',
+                command:
+                  '@binary --launcher_javabase=/usr/local/buildtools/java/jdk21 --uid= -loas_pwd_fallback_in_corp -Xms3g -Xmx8g run ...',
+              },
+            ],
+            files: [
+              {
+                name: 'kill_zombie_lab_script',
+                path: 'gs://release-resource/kill_zombie_lab.sh',
+              },
+              {
+                name: 'command_server_binary',
+                path: 'gs://release-resource/mobileharness/command_server_deploy.jar',
+              },
+              {
+                name: 'binary',
+                path: 'gs://release-resource/mobileharness/lab_server_deploy_4.349.0.jar',
+              },
+              {
+                name: 'cleaner',
+                path: 'gs://release-resource/mobileharness/lab_cleaner_deploy_4.349.0.jar',
+              },
+              {
+                name: 'web_flashstation_key',
+                path: 'gs://release-resource/keys/mh_web_flashstation.json',
+              },
+              {
+                name: 'legacy_daemon_killer',
+                path: 'gs://release-resource/kill_legacy_daemon_server.sh',
+              },
+              {
+                name: 'android_tradefed_test_config',
+                path: 'gs://release-resource/keys/android_tradefed_test_config_key',
+              },
+            ],
+          },
+        },
+        {
+          name: 'release_configs',
+          version: 'v4.358.0',
+          status: '',
+          buildTime: '2025-03-14 12:00:00',
+          ports: [
+            {
+              protocol: 'TCP',
+              portNumber: 8080,
+            },
+            {
+              protocol: 'TCP',
+              portNumber: 8081,
+            },
+          ],
+          releaseDetails: createDefaultReleaseDetails(),
+        },
+        {
+          name: 'release_configs',
+          version: 'v4.357.0',
+          status: 'Current',
+          buildTime: '2025-03-13 12:00:00',
+          ports: [
+            {
+              protocol: 'TCP',
+              portNumber: 8080,
+            },
+          ],
+          releaseDetails: createDefaultReleaseDetails(),
+        },
+        {
+          name: 'release_configs',
+          version: 'v4.356.0',
+          status: '',
+          buildTime: '2025-03-12 12:00:00',
+          releaseDetails: createDefaultReleaseDetails(),
+        },
+        {
+          name: 'Host Release Config',
+          version: 'v4.355.0',
+          status: '',
+          buildTime: '2025-03-11 12:00:00',
+          releaseDetails: createDefaultReleaseDetails(),
+        },
+      ],
+    },
+  };
+}
+
 /**
  * Creates a default HostOverview with basic running status.
  */
@@ -103,6 +354,67 @@ export function createDefaultHostOverview(hostName: string): HostOverview {
   };
 }
 
+/**
+ * Creates default device actions for mock scenarios.
+ */
+export function createDeviceActions(
+  permissionState:
+    | 'NO_PERMISSION'
+    | 'USER_PERMISSION'
+    | 'GROUP_PERMISSION'
+    | 'ALL_PERMISSIONS' = 'ALL_PERMISSIONS',
+): DeviceActions {
+  const enabled = permissionState !== 'NO_PERMISSION';
+  return {
+    remoteControl: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    decommission: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    configuration: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    screenshot: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    logcat: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    flash: {
+      params: {
+        deviceType: 'AndroidRealDevice',
+        requiredDimensions: 'required_dimensions',
+      },
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+    quarantine: {
+      enabled,
+      visible: true,
+      tooltip: permissionState,
+      isReady: true,
+    },
+  };
+}
+
 /**
  * Creates HostActions based on the host state.
  * @param status The status of the host (RUNNING, STOPPED, MISSING, ERROR, etc.)
@@ -164,7 +476,7 @@ export function createLabServerActions(
         : isCoreLab
           ? 'Cannot release in a Shared Lab'
           : '',
-      isReady: false,
+      isReady: true,
     },
     start: {
       enabled: !isRunning && !isMissing && actionEnabled,
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/index.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/index.ts
index d50b3cea22..13432aab96 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/index.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/index.ts
@@ -42,6 +42,7 @@ import {SCENARIO_HOST_DISCOVERY_HIDDEN} from './hosts/08_device_discovery_hidden
 import {SCENARIO_HOST_DEVICE_CONFIG_HIDDEN} from './hosts/09_device_config_hidden';
 import {SCENARIO_HOST_DEVICE_CONFIG_WIFI_DIMENSIONS_ONLY} from './hosts/10_device_config_wifi_dimensions_only';
 import {SCENARIO_HOST_COMING_SOON} from './hosts/11_coming_soon';
+import {SCENARIO_HOST_NO_VALID_VERSIONS} from './hosts/12_no_valid_versions';
 import {SCENARIO_HOST_X_PROD} from './hosts/host_x_prod';
 import {SCENARIO_HOST_Z_PROD} from './hosts/host_z_prod';
 import {
@@ -117,6 +118,7 @@ export const MOCK_HOST_SCENARIOS: MockHostScenario[] = [
   SCENARIO_HOST_X_PROD,
   SCENARIO_HOST_Z_PROD,
   SCENARIO_HOST_COMING_SOON,
+  SCENARIO_HOST_NO_VALID_VERSIONS,
   SCENARIO_RC_ALL_VALID,
   SCENARIO_RC_MIXED_ALL,
   SCENARIO_RC_PROXY_MISMATCH,
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/models.ts b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/models.ts
index 83e1a801ba..ecdb2e9e97 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/models.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/core/services/mock_data/models.ts
@@ -9,7 +9,10 @@ import {
   RecoveryTaskStats,
   TestResultStats,
 } from '../../models/device_stats';
-import {HostActions} from '../../models/host_action';
+import {
+  HostActions,
+  PreflightLabServerReleaseResponse,
+} from '../../models/host_action';
 import {GetHostConfigResult} from '../../models/host_config_models';
 import {DeviceSummary, HostOverview} from '../../models/host_overview';
 
@@ -51,4 +54,5 @@ export interface MockHostScenario {
   overview?: HostOverview;
   deviceSummaries?: DeviceSummary[];
   actions: HostActions;
+  releaseResponse?: PreflightLabServerReleaseResponse;
 }
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ng.html
new file mode 100644
index 0000000000..e8e62dc90e
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ng.html
@@ -0,0 +1,4 @@
+<div class="permission-box">
+  <p>You don't have the permission to perform this action on <strong>{{hostName}}</strong>.</p>
+  <p>Please check access in the <a class="permission-page-link" (click)="navigateToPermissionsPage()">host permission page</a> or contact the host administrator.</p>
+</div>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.scss b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.scss
new file mode 100644
index 0000000000..cf0dafe97e
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.scss
@@ -0,0 +1,19 @@
+.permission-box {
+  display: flex;
+  flex-direction: column;
+  gap: 1.25rem;
+
+
+  p {
+    text-align: center;
+    color: #4b5563;
+    font-size: 0.875rem;
+    line-height: 1.625;
+    margin: 0;
+    max-width: 28rem;
+  }
+
+  .permission-page-link {
+    cursor: pointer;
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.spec.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.spec.ts
new file mode 100644
index 0000000000..0b95144277
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.spec.ts
@@ -0,0 +1,51 @@
+import {ComponentFixture, TestBed} from '@angular/core/testing';
+import {MatDialog} from '@angular/material/dialog';
+import {
+  MatTestDialogOpener,
+  MatTestDialogOpenerModule,
+} from '@angular/material/dialog/testing';
+import {NoopAnimationsModule} from '@angular/platform-browser/animations';
+
+import {ActionNoPermissionContent} from './action_no_permission_content';
+
+describe('ActionNoPermissionContent', () => {
+  let component: ActionNoPermissionContent;
+  let fixture: ComponentFixture<MatTestDialogOpener<ActionNoPermissionContent>>;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      imports: [
+        ActionNoPermissionContent,
+        NoopAnimationsModule,
+        MatTestDialogOpenerModule,
+      ],
+    }).compileComponents();
+
+    fixture = TestBed.createComponent(
+      MatTestDialogOpener.withComponent(ActionNoPermissionContent),
+    );
+    fixture.detectChanges();
+    component = fixture.componentInstance.dialogRef.componentInstance;
+    component.hostName = 'test-host';
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+
+  it('should display a no permission message', () => {
+    const contentEl = document.querySelector(
+      'app-action-no-permission-content',
+    );
+    expect(contentEl?.textContent).toContain("don't have the permission");
+  });
+
+  it('should close dialog when navigating to permissions page', () => {
+    const matDialog = TestBed.inject(MatDialog);
+    spyOn(matDialog, 'open');
+    spyOn(fixture.componentInstance.dialogRef, 'close');
+    component.navigateToPermissionsPage();
+    expect(fixture.componentInstance.dialogRef.close).toHaveBeenCalled();
+  });
+});
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ts
new file mode 100644
index 0000000000..55d835bd23
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/action_no_permission_content/action_no_permission_content.ts
@@ -0,0 +1,31 @@
+import {CommonModule} from '@angular/common';
+import {ChangeDetectionStrategy, Component, inject, Input} from '@angular/core';
+import {MatDialog, MatDialogRef} from '@angular/material/dialog';
+import {MatIconModule} from '@angular/material/icon';
+import {HostConfig} from '../../host_config/host_config';
+
+/**
+ * Component to display "no permission" message for host actions.
+ */
+@Component({
+  selector: 'app-action-no-permission-content',
+  standalone: true,
+  imports: [CommonModule, MatIconModule],
+  templateUrl: './action_no_permission_content.ng.html',
+  styleUrls: ['./action_no_permission_content.scss'],
+  changeDetection: ChangeDetectionStrategy.OnPush,
+})
+export class ActionNoPermissionContent {
+  @Input({required: true}) hostName!: string;
+
+  private readonly dialog = inject(MatDialog);
+  private readonly dialogRef = inject(MatDialogRef);
+
+  navigateToPermissionsPage() {
+    this.dialog.open(HostConfig, {
+      data: {hostName: this.hostName},
+      autoFocus: false,
+    });
+    this.dialogRef.close();
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ng.html
new file mode 100644
index 0000000000..cdd0aaa2b6
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ng.html
@@ -0,0 +1,178 @@
+<app-dialog
+  title="Pass-through Flags"
+  subtitle="Editing startup arguments for <strong>{{ data.hostName }}</strong>"
+  type="host"
+  width="64rem"
+  height="80vh"
+  maxHeight="90vh"
+  footerType="normal">
+  <div header-prefix class="header-icon-wrapper">
+    <mat-icon>tune</mat-icon>
+  </div>
+  <mat-dialog-content class="dialog-content flags-dialog-wrapper" style="padding: 0;">
+    <div class="flags-dialog-body">
+      <!-- Main Editor Column -->
+      <div class="flags-dialog-editor-col">
+        <!-- Mode Switcher -->
+        <div class="flags-dialog-mode-switcher">
+          <p class="description-text">Configure additional startup arguments for the Lab Server binary.</p>
+          <div class="mode-buttons-group">
+            <button (click)="toggleMode(true)"
+                    [class.active]="isListMode()"
+                    class="mode-btn">
+              @if (isListMode()) {
+                <mat-icon class="mr-1">check</mat-icon>
+              }
+              <span>List View</span>
+            </button>
+            <button (click)="toggleMode(false)"
+                    [class.active]="!isListMode()"
+                    class="mode-btn">
+              @if (!isListMode()) {
+                <mat-icon class="mr-1">check</mat-icon>
+              }
+              <span>Text View</span>
+            </button>
+          </div>
+        </div>
+
+        <div class="editor-container">
+          <!-- List Mode View -->
+          @if (isListMode()) {
+            <div class="list-view-container">
+              <!-- Add Flag Input -->
+              <div class="add-input-row">
+                <mat-form-field appearance="outline" class="flag-form-field" subscriptSizing="dynamic">
+                  <mat-icon matPrefix>add</mat-icon>
+                  <input matInput
+                         [(ngModel)]="addInput"
+                         (keydown.enter)="addFlag()"
+                         placeholder="Type flag, e.g. --debug_mode=true"
+                         class="flag-input"
+                         aria-label="Type pass-through flag">
+                </mat-form-field>
+                <button mat-stroked-button
+                        (click)="addFlag()"
+                        [disabled]="!addInput().trim()"
+                        class="add-btn"
+                        title="Add Flag">
+                  <mat-icon>add</mat-icon>
+                </button>
+              </div>
+
+              <!-- Current Flags List -->
+              <div class="list-header">
+                <span class="title">Current Flags</span>
+                <button (click)="clearAll()" class="clear-btn">
+                  <mat-icon>delete_sweep</mat-icon> Clear All
+                </button>
+              </div>
+
+              <div class="flags-list-wrapper">
+                @if (currentFlagsArray().length === 0) {
+                  <div class="empty-state">
+                    <div class="icon-circle">
+                      <mat-icon>data_array</mat-icon>
+                    </div>
+                    <p class="empty-title">No flags configured</p>
+                    <p class="empty-subtitle">Use the input above or choose a preset from the side to get started.</p>
+                  </div>
+                } @else {
+                  <ul class="divide-y">
+                    @for (flag of displayedFlags(); track $index) {
+                      <li class="flag-item">
+                        <div class="flag-content">
+                          <span class="flag-text">{{ flag.name }}</span>
+                          @if (flag.description) {
+                            <div class="flag-desc">
+                              <mat-icon>subdirectory_arrow_right</mat-icon>
+                              <span>{{ flag.description }}</span>
+                            </div>
+                          }
+                        </div>
+                        <button (click)="removeFlag($index)" class="delete-btn" title="Remove flag">
+                          <mat-icon>delete_outline</mat-icon>
+                        </button>
+                      </li>
+                    }
+                  </ul>
+                }
+              </div>
+            </div>
+          } @else {
+            <!-- Textarea Mode View -->
+            <div class="textarea-container">
+              <textarea [ngModel]="rawTextFlags()"
+                        (ngModelChange)="updateFlagsFromText($event)"
+                        class="flags-textarea custom-scrollbar"
+                        placeholder="Enter flags separated by spaces, e.g.\n--nomute_android --noandroid_device_daemon"></textarea>
+            </div>
+          }
+        </div>
+      </div>
+
+      <!-- Right Column: Presets -->
+      <div class="flags-dialog-presets-col">
+        <div class="presets-header">
+          <div class="header-title">
+            <mat-icon>auto_awesome</mat-icon>
+            <h3>Quick Presets</h3>
+          </div>
+          <p class="header-subtitle">Common configurations for rapid input.</p>
+        </div>
+        <div class="presets-list custom-scrollbar">
+          @if (isLoadingPresets()) {
+            <div class="loading-spinner">
+              <mat-progress-spinner mode="indeterminate" diameter="24"></mat-progress-spinner>
+            </div>
+          } @else if (presets().length === 0) {
+            <div class="empty-presets">
+              No recommended flags found.
+            </div>
+          } @else if (filteredPresets().length === 0) {
+            <div class="empty-presets">
+              No matching presets found.
+            </div>
+          } @else {
+            @for (preset of displayedPresets(); track preset.name) {
+              <div class="preset-card">
+                <div class="card-header">
+                  <span class="preset-name">{{ preset.name }}</span>
+                  <button (click)="appendPreset(preset)"
+                          [disabled]="preset.isAdded"
+                          class="append-btn"
+                          [title]="preset.isAdded ? 'Already added' : 'Add to flags'">
+                    @if (preset.isAdded) {
+                      <mat-icon>check</mat-icon>
+                    } @else {
+                      <mat-icon>add</mat-icon>
+                    }
+                  </button>
+                </div>
+                <div class="preset-cmd">{{ preset.cmd }}</div>
+                <div class="preset-desc">{{ preset.description }}</div>
+              </div>
+            }
+          }
+        </div>
+      </div>
+    </div>
+  </mat-dialog-content>
+
+  <ng-template #actionsTemplate>
+    <div class="footer-actions">
+      @if (errorMessage()) {
+        <span class="error-text">{{ errorMessage() }}</span>
+      }
+      <button class="secondary-button" (click)="discardChanges()" [disabled]="!isDirty() || isSaving()">Discard Changes</button>
+      <button class="primary-button" (click)="save()" [disabled]="!isDirty() || isSaving()">
+        @if (isSaving()) {
+          <mat-progress-spinner mode="indeterminate" diameter="16" class="button-spinner"></mat-progress-spinner>
+          Saving...
+        } @else {
+          Save
+        }
+      </button>
+    </div>
+  </ng-template>
+</app-dialog>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.scss b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.scss
new file mode 100644
index 0000000000..ed646dd446
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.scss
@@ -0,0 +1,575 @@
+@use '@angular/material' as mat;
+@use  '../../../../../shared/styles/common.scss' as common;
+
+.header-icon-wrapper {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 2.5rem;
+  height: 2.5rem;
+  border-radius: 0.75rem;
+  background-color: #eff6ff;
+  color: #2563eb;
+  margin-right: 12px;
+  border: 1px solid #dbeafe;
+
+  mat-icon {
+    font-size: 20px;
+    width: 20px;
+    height: 20px;
+  }
+}
+
+.flags-dialog-wrapper {
+  @include common.shared-scrollbar-style();
+
+  .flags-dialog-body {
+    display: flex;
+    height: 100%;
+    overflow: hidden;
+    letter-spacing: normal;
+  }
+
+  .flags-dialog-editor-col {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    padding: 1.5rem;
+    overflow: hidden;
+  }
+
+  .flags-dialog-mode-switcher {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    margin-bottom: 1.5rem;
+
+    .description-text {
+      font-size: 0.8125rem;
+      color: #4b5563;
+      font-weight: 500;
+    }
+
+    .mode-buttons-group {
+      display: flex;
+      border: 1px solid #d1d5db;
+      border-radius: 9999px;
+      overflow: hidden;
+      height: 2.25rem;
+      box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
+
+      .mode-btn {
+        flex: 1;
+        min-width: 7.5rem;
+        padding: 0 1.25rem;
+        display: flex;
+        align-items: center;
+        justify-content: center;
+        font-size: 0.875rem;
+        white-space: nowrap;
+        font-weight: 500;
+        transition: all 0.2s;
+        background: transparent;
+        border: none;
+        cursor: pointer;
+        color: #4b5563;
+
+        mat-icon {
+          font-size: 1.125rem;
+          width: 1.125rem;
+          height: 1.125rem;
+          margin-right: 0.25rem;
+        }
+
+        &:first-child {
+          border-right: 1px solid #d1d5db;
+        }
+
+        &:hover:not(.active) {
+          background-color: #f9fafb;
+        }
+
+        &.active {
+          background-color: #dbeafe;
+          color: #1e3a8a;
+        }
+      }
+    }
+  }
+
+  .editor-container {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    min-height: 0;
+    background-color: rgba(248, 250, 252, 0.5);
+    border-radius: 1rem;
+    border: 1px solid #e2e8f0;
+    overflow: hidden;
+    position: relative;
+  }
+
+  .list-view-container {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    min-height: 0;
+    padding: 1rem;
+
+    .add-input-row {
+      display: flex;
+      gap: 0.5rem;
+      margin-bottom: 1rem;
+
+      .flag-form-field {
+        flex: 1;
+
+        mat-icon {
+          font-size: 1.125rem;
+          width: 1.125rem;
+          height: 1.125rem;
+          padding-right: 0.25rem;
+        }
+      }
+
+      .add-btn {
+        display: inline-flex;
+        align-items: center;
+        justify-content: center;
+        width: 2.25rem;
+        height: 2.75rem;
+        min-width: 2.75rem;
+        padding: 0;
+        background-color: #eff6ff;
+        color: #2563eb;
+        border-radius: 0.5rem;
+        border: 1px solid #dbeafe;
+        cursor: pointer;
+        transition: all 0.2s;
+
+        &:hover:not(:disabled) {
+          background-color: #2563eb;
+          color: white;
+        }
+
+        &:disabled {
+          background-color: #f9fafb;
+          color: #d1d5db;
+          border-color: #e5e7eb;
+          cursor: not-allowed;
+        }
+
+        mat-icon {
+          margin: 0;
+        }
+      }
+    }
+
+    .list-header {
+      display: flex;
+      justify-content: space-between;
+      align-items: center;
+      margin-bottom: 0.75rem;
+      padding: 0 0.25rem;
+
+      .title {
+        font-size: 0.75rem;
+        font-weight: 700;
+        color: #6b7280;
+        text-transform: uppercase;
+        letter-spacing: 0.05em;
+      }
+
+      .clear-btn {
+        font-size: 0.6875rem;
+        font-weight: 700;
+        color: #dc2626;
+        background: transparent;
+        border: none;
+        cursor: pointer;
+        display: flex;
+        align-items: center;
+        gap: 0.25rem;
+        padding: 0.25rem 0.5rem;
+        border-radius: 0.25rem;
+
+        &:hover {
+          background-color: #fee2e2;
+        }
+
+        mat-icon {
+          font-size: 0.875rem;
+          width: 0.875rem;
+          height: 0.875rem;
+        }
+      }
+    }
+
+    .flags-list-wrapper {
+      flex: 1;
+      overflow-y: auto;
+      border-radius: 0.75rem;
+      border: 1px solid #e5e7eb;
+      background-color: white;
+
+      .empty-state {
+        height: 100%;
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+        justify-content: center;
+        text-align: center;
+        letter-spacing: normal;
+
+        .icon-circle {
+          width: 3.5rem;
+          height: 3.5rem;
+          background-color: #f9fafb;
+          color: #d1d5db;
+          border-radius: 9999px;
+          display: flex;
+          align-items: center;
+          justify-content: center;
+
+          mat-icon {
+            font-size: 1.75rem;
+            width: 1.75rem;
+            height: 1.75rem;
+          }
+        }
+
+        .empty-title {
+          font-size: 0.875rem;
+          line-height: 1.25rem;
+          font-weight: 500;
+          color: #111827;
+        }
+
+        .empty-subtitle {
+          font-size: 0.75rem;
+          line-height: 1rem;
+          color: #6b7280;
+          margin-top: 0.25rem;
+          max-width: 12.5rem;
+        }
+      }
+
+      .divide-y {
+        list-style: none;
+        padding: 0;
+        margin: 0;
+
+        .flag-item {
+          display: flex;
+          justify-content: space-between;
+          align-items: center;
+          padding: 1rem;
+          border-bottom: 1px solid #f3f4f6;
+
+          &:last-child {
+            border-bottom: none;
+          }
+
+          &:hover {
+            background-color: rgba(239, 246, 255, 0.3);
+          }
+
+          .flag-content {
+            min-width: 0;
+            flex-grow: 1;
+            padding-right: 1rem;
+          }
+
+          .flag-text {
+            font-family: monospace;
+            font-size: 0.8125rem;
+            color: #111827;
+            font-weight: 500;
+            word-break: break-all;
+          }
+
+          .flag-desc {
+            font-size: 0.625rem;
+            color: #6b7280;
+            display: flex;
+            align-items: center;
+            gap: 0.25rem;
+
+            mat-icon {
+              font-size: 0.875rem;
+              width: 0.875rem;
+              height: 0.875rem;
+              color: #9ca3af;
+            }
+
+            span {
+              line-height: normal;
+            }
+          }
+
+          .delete-btn {
+            color: #d1d5db;
+            background: transparent;
+            border: none;
+            cursor: pointer;
+            padding: 0.375rem;
+            border-radius: 0.5rem;
+            transition: all 0.2s;
+            height: 2.5rem;
+
+            &:hover {
+              color: #ef4444;
+              background-color: #fee2e2;
+            }
+
+            mat-icon {
+              font-size: 1.125rem;
+              width: 1.125rem;
+              height: 1.125rem;
+            }
+          }
+        }
+      }
+    }
+  }
+
+  .textarea-container {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    padding: 1rem;
+    height: 100%;
+
+    .flags-textarea {
+      height: 100%;
+      padding: 1.25rem;
+      background-color: #0f172a;
+      color: #93c5fd;
+      font-family: monospace;
+      font-size: 0.875rem;
+      border-radius: 0.75rem;
+      border: 1px solid #1e293b;
+      resize: none;
+      line-height: 1.625;
+
+      &:focus {
+        outline: none;
+        border-color: #2563eb;
+        box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.2);
+      }
+    }
+  }
+
+  .flags-dialog-presets-col {
+    width: 20rem;
+    background-color: rgba(249, 250, 251, 0.8);
+    border-left: 1px solid #e5e7eb;
+    display: flex;
+    flex-direction: column;
+    overflow: hidden;
+
+    .presets-header {
+      padding: 1.25rem;
+      border-bottom: 1px solid #e5e7eb;
+      background-color: rgba(255, 255, 255, 0.5);
+      backdrop-filter: blur(4px);
+      flex-shrink: 0;
+
+      .header-title {
+        display: flex;
+        align-items: center;
+        gap: 0.5rem;
+        margin-bottom: 0.25rem;
+
+        h3 {
+          font-weight: 700;
+          color: #1f2937;
+          font-size: 0.75rem;
+          margin: 0;
+        }
+
+        mat-icon {
+          color: #f59e0b;
+          font-size: 1.125rem;
+          width: 1.125rem;
+          height: 1.125rem;
+        }
+      }
+
+      .header-subtitle {
+        font-size: 0.625rem;
+        color: #6b7280;
+        line-height: 1.25;
+        margin-bottom: 0;
+      }
+    }
+
+    .presets-list {
+      padding: 1rem;
+      overflow-y: auto;
+      flex: 1;
+      display: flex;
+      flex-direction: column;
+      gap: 0.75rem;
+
+      .loading-spinner {
+        display: flex;
+        justify-content: center;
+        padding: 2rem 0;
+      }
+
+      .empty-presets {
+        text-align: center;
+        font-size: 0.75rem;
+        color: #9ca3af;
+        padding: 3rem 1rem;
+        font-style: italic;
+      }
+
+      .preset-card {
+        background-color: white;
+        border: 1px solid #e5e7eb;
+        border-radius: 0.75rem;
+        padding: 0.75rem;
+        box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
+        transition: all 0.2s;
+
+        &:hover {
+          border-color: #bfdbfe;
+        }
+
+        .card-header {
+          display: flex;
+          justify-content: space-between;
+          align-items: flex-start;
+          margin-bottom: 0.5rem;
+
+          .preset-name {
+            font-weight: 700;
+            color: #1f2937;
+            font-size: 0.6875rem;
+            line-height: 1.25;
+            padding-right: 0.5rem;
+          }
+
+          .append-btn {
+            flex-shrink: 0;
+            display: flex;
+            align-items: center;
+            justify-content: center;
+            width: 1.75rem;
+            height: 1.75rem;
+            background-color: #eff6ff;
+            color: #2563eb;
+            border-radius: 0.5rem;
+            border: 1px solid #dbeafe;
+            cursor: pointer;
+            transition: all 0.2s;
+
+            &:hover:not(:disabled) {
+              background-color: #2563eb;
+              color: white;
+            }
+
+            &:disabled {
+              background-color: #f3f4f6;
+              color: #9ca3af;
+              border-color: #e5e7eb;
+              cursor: not-allowed;
+            }
+
+            mat-icon {
+              font-size: 0.875rem;
+              width: 0.875rem;
+              height: 0.875rem;
+            }
+          }
+        }
+
+        .preset-cmd {
+          font-family: monospace;
+          font-size: 0.5625rem;
+          color: #4b5563;
+          background-color: #f9fafb;
+          padding: 0.5rem;
+          border-radius: 0.25rem;
+          border: 1px solid #f3f4f6;
+          margin-bottom: 0.5rem;
+          word-break: break-all;
+          line-height: 1.4;
+        }
+
+        .preset-desc {
+          font-size: 0.5625rem;
+          color: #9ca3af;
+          line-height: 1.25;
+          font-style: italic;
+        }
+      }
+    }
+  }
+}
+
+.footer-actions {
+  display: flex;
+  justify-content: flex-end;
+  align-items: center;
+  width: 100%;
+  gap: 0.5rem;
+
+  button {
+    padding: 0.5rem 1rem;
+    border-radius: 0.375rem;
+    font-weight: 500;
+    font-size: 0.875rem;
+    cursor: pointer;
+    transition: all 0.2s;
+  }
+
+  .primary-button {
+    background-color: #0b57d0;
+    color: white;
+    border: none;
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    gap: 0.5rem;
+
+    &:hover:not(:disabled) {
+      background-color: #0a4cb8;
+    }
+
+    &:disabled {
+      background-color: #e2e8f0;
+      color: #94a3b8;
+      cursor: not-allowed;
+    }
+  }
+
+  .secondary-button {
+    background-color: white;
+    color: #0b57d0;
+    border: 1px solid #c2c2c2;
+
+    &:hover:not(:disabled) {
+      background-color: #f0f5fe;
+    }
+
+    &:disabled {
+      background-color: white;
+      color: #94a3b8;
+      border-color: #e2e8f0;
+      cursor: not-allowed;
+    }
+  }
+
+  .tertiary-button {
+    background-color: transparent;
+    color: #475569;
+    border: none;
+
+    &:hover {
+      background-color: #f1f5f9;
+    }
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ts
new file mode 100644
index 0000000000..9ae58b97f1
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/flags_dialog/flags_dialog.ts
@@ -0,0 +1,251 @@
+import {CommonModule} from '@angular/common';
+import {
+  ChangeDetectionStrategy,
+  Component,
+  computed,
+  inject,
+  OnInit,
+  signal,
+  ViewEncapsulation,
+} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {MatButtonModule} from '@angular/material/button';
+import {
+  MAT_DIALOG_DATA,
+  MatDialogModule,
+  MatDialogRef,
+} from '@angular/material/dialog';
+import {MatFormFieldModule} from '@angular/material/form-field';
+import {MatIconModule} from '@angular/material/icon';
+import {MatInputModule} from '@angular/material/input';
+import {MatProgressSpinnerModule} from '@angular/material/progress-spinner';
+import {take} from 'rxjs/operators';
+
+import {PopularFlag} from '../../../../../core/models/host_action';
+import {HOST_SERVICE} from '../../../../../core/services/host/host_service';
+import {Dialog} from '../../../../../shared/components/config_common/dialog/dialog';
+
+/**
+ * Structure for passing data including host identity and current flags to FlagsDialog.
+ */
+export interface FlagsDialogData {
+  hostName: string;
+  currentFlags: string;
+}
+/**
+ * Handles configuration and synchronization operations for Pass-through Flags in the Lab Console.
+ */
+@Component({
+  selector: 'app-flags-dialog',
+  standalone: true,
+  imports: [
+    CommonModule,
+    FormsModule,
+    MatButtonModule,
+    MatDialogModule,
+    MatFormFieldModule,
+    MatIconModule,
+    MatInputModule,
+    MatProgressSpinnerModule,
+    Dialog,
+  ],
+  templateUrl: './flags_dialog.ng.html',
+  styleUrl: './flags_dialog.scss',
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  encapsulation: ViewEncapsulation.None,
+})
+export class FlagsDialog implements OnInit {
+  readonly data = inject<FlagsDialogData>(MAT_DIALOG_DATA);
+  private readonly dialogRef = inject(MatDialogRef<FlagsDialog>);
+  private readonly hostService = inject(HOST_SERVICE);
+
+  readonly isListMode = signal(true);
+  readonly currentFlagsArray = signal<string[]>([]);
+  readonly initialFlagsArray = signal<string[]>([]);
+  readonly presets = signal<PopularFlag[]>([]);
+  readonly isLoadingPresets = signal(false);
+  readonly isSaving = signal(false);
+  readonly errorMessage = signal('');
+  readonly addInput = signal('');
+  readonly filterText = signal('');
+  readonly rawTextFlags = signal('');
+
+  readonly isDirty = computed(() => {
+    const currentFlags = this.isListMode()
+      ? this.currentFlagsArray().join(' ')
+      : this.rawTextFlags();
+    const normalizedCurrentStr = this.splitFlags(currentFlags).join(' ');
+    const normalizedInitialStr = this.initialFlagsArray().join(' ');
+    return normalizedCurrentStr !== normalizedInitialStr;
+  });
+
+  readonly filteredPresets = computed(() => {
+    const filter = (this.addInput() || '').toLowerCase();
+    if (!filter) return this.presets();
+    return this.presets().filter(
+      (p) =>
+        (p.name || '').toLowerCase().includes(filter) ||
+        (p.description || '').toLowerCase().includes(filter) ||
+        (p.cmd || '').toLowerCase().includes(filter),
+    );
+  });
+
+  private splitFlags(input: string): string[] {
+    if (!input) return [];
+    return input
+      .trim()
+      .split(/\s+(?=--)/)
+      .filter(Boolean);
+  }
+
+  readonly flagDescriptions = computed(() => {
+    const entries = this.presets().flatMap((p) => {
+      const flags = this.splitFlags(p.cmd);
+      const desc = flags.length === 1 ? p.description : `Part of: ${p.name}`;
+      return flags.map((f) => [f, desc] as [string, string]);
+    });
+    return new Map<string, string>(entries);
+  });
+
+  readonly displayedFlags = computed(() => {
+    const map = this.flagDescriptions();
+    return this.currentFlagsArray().map((flag) => {
+      let description = map.get(flag) || '';
+      if (!description) {
+        const baseFlag = flag.split('=')[0];
+        description = map.get(baseFlag) || '';
+      }
+      return {name: flag, description};
+    });
+  });
+
+  readonly displayedPresets = computed(() => {
+    const activeFlags = this.isListMode()
+      ? this.currentFlagsArray()
+      : this.splitFlags(this.rawTextFlags());
+    const currentSet = new Set(activeFlags);
+    return this.filteredPresets().map((p) => {
+      const presetFlags = this.splitFlags(p.cmd);
+      const isAdded =
+        presetFlags.length > 0 && presetFlags.every((f) => currentSet.has(f));
+      return {...p, isAdded};
+    });
+  });
+
+  ngOnInit() {
+    this.parseInitialFlags();
+    this.loadPresets();
+  }
+
+  parseInitialFlags() {
+    const flags = this.data.currentFlags
+      ? this.splitFlags(this.data.currentFlags)
+      : [];
+    this.rawTextFlags.set(this.data.currentFlags);
+    this.currentFlagsArray.set([...flags]);
+    this.initialFlagsArray.set([...flags]);
+  }
+
+  updateFlagsFromText(text: string) {
+    this.rawTextFlags.set(text);
+  }
+
+  loadPresets() {
+    this.isLoadingPresets.set(true);
+    this.hostService
+      .getPopularFlags(this.data.hostName)
+      .pipe(take(1))
+      .subscribe({
+        next: (response) => {
+          this.presets.set(response?.flags || []);
+          this.isLoadingPresets.set(false);
+        },
+        error: () => {
+          this.isLoadingPresets.set(false);
+        },
+      });
+  }
+
+  toggleMode(isList: boolean) {
+    if (this.isListMode() && !isList) {
+      // Switching from List to Text: Update rawTextFlags from current array
+      this.rawTextFlags.set(this.currentFlagsArray().join(' '));
+    } else if (!this.isListMode() && isList) {
+      // Switching from Text to List: Parse rawTextFlags into currentFlagsArray
+      const flags = this.rawTextFlags()
+        ? this.splitFlags(this.rawTextFlags())
+        : [];
+      this.currentFlagsArray.set(flags);
+    }
+    this.isListMode.set(isList);
+  }
+
+  addFlag() {
+    const val = this.addInput().trim();
+    if (val) {
+      const newFlags = this.splitFlags(val);
+      this.currentFlagsArray.update((flags) => [...flags, ...newFlags]);
+      this.addInput.set('');
+    }
+  }
+
+  removeFlag(index: number) {
+    this.currentFlagsArray.update((flags) =>
+      flags.filter((_, i) => i !== index),
+    );
+  }
+
+  appendPreset(preset: PopularFlag) {
+    if (this.isListMode()) {
+      const newFlags = this.splitFlags(preset.cmd);
+      this.currentFlagsArray.update((flags) => [...flags, ...newFlags]);
+    } else {
+      this.rawTextFlags.update((text) => {
+        const trimmed = text.trim();
+        return trimmed ? `${trimmed} ${preset.cmd}` : preset.cmd;
+      });
+    }
+  }
+
+  clearAll() {
+    this.currentFlagsArray.set([]);
+  }
+
+  discardChanges() {
+    this.rawTextFlags.set(this.initialFlagsArray().join(' '));
+    this.currentFlagsArray.set([...this.initialFlagsArray()]);
+  }
+
+  save() {
+    const finalString = this.isListMode()
+      ? this.currentFlagsArray().join(' ').trim()
+      : this.rawTextFlags().trim();
+
+    // If in text mode, re-parse to ensure currentFlagsArray is in sync
+    if (!this.isListMode()) {
+      const flags = finalString ? this.splitFlags(finalString) : [];
+      this.currentFlagsArray.set(flags);
+    }
+
+    this.isSaving.set(true);
+    this.errorMessage.set('');
+
+    this.hostService
+      .updatePassThroughFlags(this.data.hostName, finalString)
+      .pipe(take(1))
+      .subscribe({
+        next: () => {
+          this.isSaving.set(false);
+          this.dialogRef.close(finalString);
+        },
+        error: (err: Error) => {
+          this.isSaving.set(false);
+          this.errorMessage.set(err.message || 'Failed to save flags');
+        },
+      });
+  }
+
+  close() {
+    this.dialogRef.close();
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ng.html
index 5af7fecef3..9c60c9544d 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ng.html
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ng.html
@@ -47,10 +47,14 @@
         @if (actions.release.visible) {
           <button
             (click)="actions.release.isReady ? onRelease() : showComingSoonPopup('Release')"
-            [disabled]="!actions.release.enabled"
+            [disabled]="!actions.release.enabled || isOpeningReleaseDialog()"
             [matTooltip]="actions.release.tooltip"
           >
-              <mat-icon>upgrade</mat-icon>
+              @if (isOpeningReleaseDialog()) {
+                <mat-progress-spinner mode="indeterminate" diameter="18" class="operation-spinner"></mat-progress-spinner>
+              } @else {
+                <mat-icon>upgrade</mat-icon>
+              }
               <span class="operation-text">Release</span>
           </button>
         }
@@ -141,43 +145,22 @@
                 >help_outline</mat-icon
               >
             </dt>
-            <dd [class.grid-tight-dd]="!isEditingFlags()">
-              @if(isEditingFlags()) {
-                <div class="flags-edit-container">
-                  <textarea
-                    [(ngModel)]="editedFlags"
-                    class="flags-textarea"
-                    rows="5"
-                    placeholder="Enter flags..."
-                  ></textarea>
-                  <div class="flags-edit-actions">
-                    <button (click)="cancelEditFlags()" class="flags-edit-button cancel" [disabled]="isSavingFlags()">Cancel</button>
-                    <button (click)="saveFlags()" class="flags-edit-button save" [disabled]="isSavingFlags()">
-                      @if (isSavingFlags()) {
-                        <mat-progress-spinner mode="indeterminate" diameter="16" class="button-spinner"></mat-progress-spinner>
-                        Saving...
-                      } @else {
-                        Save
-                      }
-                    </button>
-                  </div>
-                </div>
+            <dd class="grid-tight-dd">
+              @if (passThroughFlags()) {
+                <div class="monospace-block">{{ passThroughFlags() }}</div>
               } @else {
-                @if (host.labServer.passThroughFlags) {
-                  <div class="monospace-block">{{ host.labServer.passThroughFlags }}</div>
-                } @else {
-                  <span class="text-gray-500">None</span>
-                }
-                @if (updateFlags.visible) {
-                  <button
-                    mat-icon-button
-                    (click)="updateFlags.isReady ? startEditFlags() : showComingSoonPopup('Release')"
-                    [disabled]="!updateFlags.enabled"
-                    [matTooltip]="'Edit Pass Through Flags'"
-                    class="edit-flags-button">
-                    <mat-icon>edit</mat-icon>
-                  </button>
-                }
+                <span class="text-gray-500">None</span>
+              }
+
+              @if (updateFlags.visible) {
+                <button
+                  mat-icon-button
+                  (click)="updateFlags.isReady ? openFlagsDialog() : showComingSoonPopup('Pass Through Flags')"
+                  [disabled]="!updateFlags.enabled"
+                  [matTooltip]="updateFlags.tooltip || 'Edit Pass Through Flags'"
+                  class="edit-flags-button">
+                  <mat-icon>edit</mat-icon>
+                </button>
               }
             </dd>
           }
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ts
index 5f02a049fb..2f25ed267b 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/host_overview.ts
@@ -69,7 +69,11 @@ import {RemoteControlService} from '../../../../shared/services/remote_control_s
 import {SnackBarService} from '../../../../shared/services/snackbar_service';
 import {dateUtils} from '../../../../shared/utils/date_utils';
 import {objectUtils} from '../../../../shared/utils/object_utils';
+import {ActionNoPermissionContent} from './action_no_permission_content/action_no_permission_content';
 import {DecommissionContent} from './decommission_content/decommission_content';
+import {FlagsDialog} from './flags_dialog/flags_dialog';
+import {NoValidVersionsContent} from './no_valid_versions_content/no_valid_versions_content';
+import {ReleaseDialog} from './release_dialog/release_dialog';
 
 const HEALTH_SEMANTIC_MAP: Record<
   string,
@@ -197,9 +201,7 @@ export class HostOverviewPage implements OnChanges {
     );
   });
 
-  isEditingFlags = signal(false);
-  editedFlags = '';
-  isSavingFlags = signal(false);
+  readonly passThroughFlags = signal<string>('');
 
   deviceDataSource = new MatTableDataSource<DeviceSummary>();
   selection = new SelectionModel<DeviceSummary>(true, []);
@@ -220,6 +222,7 @@ export class HostOverviewPage implements OnChanges {
   deviceFilterValue = '';
   isDeviceLoading = signal(false);
   expandedElement = signal<DeviceSummary | null>(null);
+  isOpeningReleaseDialog = signal(false);
 
   // --- Dimensions Overlay State ---
   activeOverlay = signal<{
@@ -355,6 +358,7 @@ export class HostOverviewPage implements OnChanges {
   ngOnChanges(changes: SimpleChanges) {
     if (changes['host']) {
       this.selection.clear();
+      this.passThroughFlags.set(this.host.labServer.passThroughFlags);
       this.loadDevices();
     }
   }
@@ -398,50 +402,45 @@ export class HostOverviewPage implements OnChanges {
   }
 
   // Flags editing
-  startEditFlags() {
-    this.editedFlags = this.host.labServer.passThroughFlags;
-    this.isEditingFlags.set(true);
-  }
-
-  cancelEditFlags() {
-    this.isEditingFlags.set(false);
-  }
-
-  saveFlags() {
-    if (this.editedFlags === this.host.labServer.passThroughFlags) {
-      this.isEditingFlags.set(false);
-      return;
-    }
+  openFlagsDialog() {
+    const dialogRef = this.dialog.open(FlagsDialog, {
+      data: {
+        hostName: this.host.hostName,
+        currentFlags: this.passThroughFlags(),
+      },
+      width: '72rem',
+      maxHeight: '90vh',
+      autoFocus: false,
+    });
 
-    this.isSavingFlags.set(true);
-    this.hostService
-      .updatePassThroughFlags(this.host.hostName, this.editedFlags)
+    dialogRef
+      .afterClosed()
       .pipe(takeUntilDestroyed(this.destroyRef))
-      .subscribe({
-        next: () => {
-          this.host.labServer.passThroughFlags = this.editedFlags;
-          this.isEditingFlags.set(false);
-          this.isSavingFlags.set(false);
+      .subscribe((result) => {
+        if (
+          typeof result === 'string' &&
+          result !== 'close' &&
+          result !== 'cancel'
+        ) {
+          this.passThroughFlags.set(result);
+          this.host.labServer.passThroughFlags = result;
           this.showRestartDialog();
-        },
-        error: (err) => {
-          this.snackBar.showError(`Failed to save flags: ${err.message}`);
-          this.isSavingFlags.set(false);
-        },
+        }
       });
   }
 
   showRestartDialog() {
     const dialogData = {
-      title: 'Restart Required',
-      content: `Pass through flags for ${this.host.hostName} have been updated. A Lab Server restart is required for changes to take effect. Restart now?`,
-      type: 'warning',
-      primaryButtonLabel: 'Restart Now',
+      title: 'Flags Updated',
+      content: `Pass-through flags have been updated successfully. Would you like to perform a release now to apply these changes?`,
+      customIcon: 'rocket_launch',
+      primaryButtonLabel: 'Release Now',
       secondaryButtonLabel: 'Later',
     };
 
     const restartDialogRef = this.dialog.open(ConfirmDialog, {
       data: dialogData,
+      panelClass: 'confirm-dialog-panel',
       disableClose: true,
     });
 
@@ -456,7 +455,79 @@ export class HostOverviewPage implements OnChanges {
   }
 
   onRelease() {
-    this.showComingSoonPopup('Release');
+    this.isOpeningReleaseDialog.set(true);
+    this.hostService
+      .preflightLabServerRelease(this.host.hostName)
+      .pipe(takeUntilDestroyed(this.destroyRef))
+      .subscribe({
+        next: (response) => {
+          this.isOpeningReleaseDialog.set(false);
+          if (response.permissionDenied) {
+            const dialogData = {
+              title: 'No Access',
+              contentComponent: ActionNoPermissionContent,
+              contentComponentInputs: {
+                hostName: this.host.hostName,
+              },
+              type: 'error',
+              customIcon: 'lock_outline',
+              primaryButtonLabel: 'Close',
+            };
+
+            this.dialog.open(ConfirmDialog, {
+              data: dialogData,
+              panelClass: 'confirm-dialog-panel',
+            });
+
+            return;
+          }
+
+          const versions = response.ready?.versions;
+          if (!versions || versions.length === 0) {
+            const dialogData = {
+              title: 'No Valid Versions',
+              contentComponent: NoValidVersionsContent,
+              contentComponentInputs: {
+                hostName: this.host.hostName,
+              },
+              type: 'warning',
+              customIcon: 'warning_amber',
+              primaryButtonLabel: 'Close',
+            };
+
+            this.dialog.open(ConfirmDialog, {
+              data: dialogData,
+              panelClass: 'confirm-dialog-panel',
+            });
+
+            return;
+          }
+
+          const releaseDialogRef = this.dialog.open(ReleaseDialog, {
+            data: {
+              hostName: this.host.hostName,
+              releaseConfigs: versions,
+              passThroughFlags: this.passThroughFlags,
+            },
+            autoFocus: false,
+          });
+
+          releaseDialogRef
+            .afterClosed()
+            .pipe(takeUntilDestroyed(this.destroyRef))
+            .subscribe((result) => {
+              if (!result) {
+                return;
+              }
+            });
+        },
+        error: (err) => {
+          this.isOpeningReleaseDialog.set(false);
+          this.snackBar.showError(
+            `Failed to load release info: ${err.message}`,
+          );
+        },
+      });
   }
 
   onDeploy() {
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ng.html
new file mode 100644
index 0000000000..dcdbc135d4
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ng.html
@@ -0,0 +1,4 @@
+<div class="no-valid-versions-content">
+  <p>No valid release versions were found for <strong>{{hostName}}</strong>, or the version data could not be retrieved.</p>
+  <p>Please try again later or contact the host administrator if the issue persists.</p>
+</div>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.scss b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.scss
new file mode 100644
index 0000000000..e58e2e7a32
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.scss
@@ -0,0 +1,19 @@
+.no-valid-versions-content {
+  display: flex;
+  flex-direction: column;
+  gap: 1.25rem;
+
+
+  p {
+    text-align: center;
+    color: #4b5563;
+    font-size: 0.875rem;
+    line-height: 1.625;
+    margin: 0;
+    max-width: 28rem;
+  }
+
+  .no-valid-versions-content-link {
+    cursor: pointer;
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.spec.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.spec.ts
new file mode 100644
index 0000000000..4218bd318a
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.spec.ts
@@ -0,0 +1,33 @@
+import {ComponentFixture, TestBed} from '@angular/core/testing';
+import {NoopAnimationsModule} from '@angular/platform-browser/animations';
+
+import {NoValidVersionsContent} from './no_valid_versions_content';
+
+describe('NoValidVersionsContent', () => {
+  let component: NoValidVersionsContent;
+  let fixture: ComponentFixture<NoValidVersionsContent>;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      imports: [NoValidVersionsContent, NoopAnimationsModule],
+    }).compileComponents();
+
+    fixture = TestBed.createComponent(NoValidVersionsContent);
+    component = fixture.componentInstance;
+    component.hostName = 'test-host';
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+
+  it('should display the no valid versions message with hostname', () => {
+    const compiled = fixture.nativeElement as HTMLElement;
+    expect(compiled.textContent).toContain(
+      'No valid release versions were found for test-host',
+    );
+    const strongEl = compiled.querySelector('strong');
+    expect(strongEl?.textContent).toContain('test-host');
+  });
+});
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ts
new file mode 100644
index 0000000000..faa3479018
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/no_valid_versions_content/no_valid_versions_content.ts
@@ -0,0 +1,17 @@
+import {CommonModule} from '@angular/common';
+import {ChangeDetectionStrategy, Component, Input} from '@angular/core';
+
+/**
+ * Component to display "no valid release versions" message.
+ */
+@Component({
+  selector: 'app-no-valid-versions-content',
+  standalone: true,
+  imports: [CommonModule],
+  templateUrl: './no_valid_versions_content.ng.html',
+  styleUrls: ['./no_valid_versions_content.scss'],
+  changeDetection: ChangeDetectionStrategy.OnPush,
+})
+export class NoValidVersionsContent {
+  @Input({required: true}) hostName!: string;
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ng.html
new file mode 100644
index 0000000000..1464d81e9e
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ng.html
@@ -0,0 +1,310 @@
+<app-dialog
+  title="Release Lab Server"
+  subtitle="Host: {{ data.hostName }}"
+  type="host"
+  width="72rem"
+  height="750px"
+  maxHeight="90vh"
+  footerType="normal">
+  <mat-dialog-content class="dialog-content">
+    @if (currentStep() === 1) {
+      <!-- Step 1: Version Selection -->
+      <div class="step-1-container">
+        <div class="info-alert">
+          <mat-icon>
+            info_outline
+          </mat-icon>
+          <span>
+            Select a release candidate to proceed.
+          </span>
+        </div>
+        <div class="content-splitter">
+          <div class="versions-panel">
+            <table mat-table [dataSource]="availableVersions" class="versions-table">
+              <!-- Version Column -->
+              <ng-container matColumnDef="version">
+                <th mat-header-cell *matHeaderCellDef>
+                  Version
+                </th>
+                <td mat-cell *matCellDef="let element">
+                  <div class="version-label">
+                    {{ element.version }}
+                  </div>
+                  <div class="version-name">
+                    {{ element.name }}
+                  </div>
+                </td>
+              </ng-container>
+              <!-- Build Date Column -->
+              <ng-container matColumnDef="buildTime">
+                <th mat-header-cell *matHeaderCellDef>
+                  Build Date
+                </th>
+                <td mat-cell *matCellDef="let element">
+                  {{ element.buildTime | date:'shortDate' }}
+                </td>
+              </ng-container>
+              <!-- Status Column -->
+              <ng-container matColumnDef="status">
+                <th mat-header-cell *matHeaderCellDef>
+                  Status
+                </th>
+                <td mat-cell *matCellDef="let element">
+                  @if (element.status?.toLowerCase() === 'latest') {
+                    <span class="status-badge latest">
+                      Latest
+                    </span>
+                  }
+                  @if (element.status?.toLowerCase() === 'current') {
+                    <span class="status-badge current">
+                      Current
+                    </span>
+                  }
+                </td>
+              </ng-container>
+              <!-- Actions Column -->
+              <ng-container matColumnDef="actions">
+                <th mat-header-cell *matHeaderCellDef></th>
+                <td mat-cell *matCellDef="let element" class="row-actions">
+                  <button mat-icon-button title="View Details" (click)="viewDetails(element); $event.stopPropagation();">
+                    <mat-icon style="opacity: 1;">
+                      info
+                    </mat-icon>
+                  </button>
+                </td>
+              </ng-container>
+              <tr mat-header-row *matHeaderRowDef="displayedColumns"></tr>
+              <tr mat-row *matRowDef="let row; columns: displayedColumns;" class="version-row" [class.selected]="selectedVersion()?.version === row.version" (click)="selectVersion(row)">
+              </tr>
+            </table>
+          </div>
+          <!-- Manifest Side Panel -->
+          <div class="manifest-panel" [class.open]="showDetails()">
+            <div class="manifest-header">
+              <span>
+                Build Manifest
+              </span>
+              <button mat-icon-button (click)="showDetails.set(false)" title="Close Panel">
+                <mat-icon>close</mat-icon>
+              </button>
+            </div>
+            <div class="manifest-tabs">
+              <button class="tab-btn" [class.active]="currentTab() === 'metadata'" (click)="switchTab('metadata')">
+                Metadata
+              </button>
+              <button class="tab-btn" [class.active]="currentTab() === 'files'" (click)="switchTab('files')">
+                Files
+              </button>
+              <button class="tab-btn" [class.active]="currentTab() === 'commands'" (click)="switchTab('commands')">
+                Commands
+              </button>
+            </div>
+            <div class="manifest-content">
+              @if (currentTab() === 'metadata') {
+                <div class="metadata-content">
+                  <div class="detail-item">
+                    <mat-icon>tag</mat-icon>
+                    <div>
+                      <div class="label">Version</div>
+                      <div class="value">
+                        {{ selectedVersion()?.version || 'N/A' }}
+                      </div>
+                    </div>
+                  </div>
+                  <div class="detail-item">
+                    <mat-icon>label</mat-icon>
+                    <div>
+                      <div class="label">Release Name</div>
+                      <div class="value">
+                        {{ selectedVersion()?.name || 'N/A' }}
+                      </div>
+                    </div>
+                  </div>
+                  <div class="detail-item">
+                    <mat-icon>schedule</mat-icon>
+                    <div>
+                      <div class="label">Build Time</div>
+                      <div class="value">
+                        {{ selectedVersion()?.buildTime | date:'medium' }}
+                      </div>
+                    </div>
+                  </div>
+                  <div class="detail-item">
+                    <mat-icon>settings_ethernet</mat-icon>
+                    <div>
+                      <div class="label">Ports</div>
+                      <div class="value">
+                        @for (p of selectedVersion()?.ports; track p.portNumber; let last = $last) {
+                          {{ p.protocol }}:{{ p.portNumber }}{{ last ? '' : ', ' }}
+                        }
+                        @empty { N/A }
+                      </div>
+                    </div>
+                  </div>
+                  @defer (on idle) {
+                    @for (group of selectedVersion()?.releaseDetails?.changeLogs; track group.name) {
+                      <div class="changelist-section">
+                        <div class="section-title">{{ group.name }}</div>
+                        <ul>
+                          @for (c of group.items; track c) {
+                            @if (c.change) {
+                              <li>
+                                <span class="cl-number">cl/{{ c.change.cl }}</span>: {{ c.change.text }}
+                                @if (c.change.bugs && c.change.bugs.length > 0) {
+                                  <span class="bug-number">
+                                    (b/{{ c.change.bugs.join(', ') }})
+                                  </span>
+                                }
+                              </li>
+                            }
+                            @if (c.bug) {
+                              <li>
+                                <span class="cl-number">b/{{ c.bug.bug }}</span>: {{ c.bug.text }}
+                              </li>
+                            }
+                          }
+                        </ul>
+                      </div>
+                    }
+                  } @placeholder {
+                    <div class="empty-text">
+                      Loading change logs...
+                    </div>
+                  }
+                </div>
+              }
+              @if (currentTab() === 'files') {
+                <div class="files-content">
+                  @defer (on idle) {
+                    @for (file of selectedVersion()?.releaseDetails?.files; track file.name) {
+                      <div class="file-item">
+                        <div class="file-key">{{ file.name }}</div>
+                        @if (file.path) {
+                          <div class="file-value">{{ file.path }}</div>
+                        } @else {
+                          <div class="file-value not-set">Not set</div>
+                        }
+                      </div>
+                    } @empty {
+                      <div class="empty-text"> No Files </div>
+                    }
+                  } @placeholder {
+                    <div class="empty-text">
+                      Loading files...
+                    </div>
+                  }
+                </div>
+              }
+              @if (currentTab() === 'commands') {
+                <div class="commands-content">
+                  @if (hasCommands()) {
+                    @if (hasSyncCommands()) {
+                      <div class="section-title">Sync Commands</div>
+                      @for (cmd of selectedVersion()?.releaseDetails?.syncCommands; track cmd.name) {
+                        <span class="command-name">{{ cmd.name }}</span>
+                        <code class="command-block">{{ cmd.command }}</code>
+                      }
+                    }
+                    @if (hasAsyncCommands()) {
+                      <div class="section-title">Async Commands</div>
+                      @for (cmd of selectedVersion()?.releaseDetails?.asyncCommands; track cmd.name) {
+                        <span class="command-name">{{ cmd.name }}</span>
+                        <code class="command-block async">{{ cmd.command }}</code>
+                      }
+                    }
+                  } @else {
+                    <div class="empty-text"> No Commands </div>
+                  }
+                </div>
+              }
+            </div>
+          </div>
+        </div>
+      </div>
+    } @else if (currentStep() === 2) {
+      <!-- Step 2: Deployment Confirmation -->
+      <div class="step-2-container">
+        <header class="step-2-header">
+          <div class="header-icon"><mat-icon>rocket_launch</mat-icon></div>
+          <div>
+            <h3>Ready to Deploy</h3>
+            <p>Please review your deployment configuration before proceeding.</p>
+          </div>
+        </header>
+        <div class="version-summary-card">
+          <div class="left-section">
+            <div class="icon-bg"><mat-icon>label</mat-icon></div>
+            <div class="version-details">
+              <div class="label">Selected Version</div>
+              <div class="value">
+                <span class="version-str">{{ selectedVersion()?.version }}</span>
+                @if (selectedVersion()?.status?.toLowerCase() === 'latest') {
+                  <span class="status-badge latest">Latest</span>
+                }
+              </div>
+            </div>
+          </div>
+          <div class="right-section">
+            <div class="label">Build Date</div>
+            <div class="value">{{ selectedVersion()?.buildTime | date:'mediumDate' }}</div>
+          </div>
+        </div>
+        <div class="flags-section">
+          <div class="section-header">
+            <div class="title-section">
+              <span class="header-title">Pass-through Flags</span>
+              <span class="optional-badge">Optional</span>
+            </div>
+            <button mat-button class="add-flags-button" (click)="openFlagsDialog()">
+              <mat-icon>tune</mat-icon>
+              {{ tempFlags() ? 'Configure' : 'Add Flags' }}
+            </button>
+          </div>
+          @if (tempFlags()) {
+            <div class="flags-code-block">
+              <code class="flags-content">{{ tempFlags() }}</code>
+              @if (flagsModifiedThisSession()) {
+                <div class="modified-label">
+                  <mat-icon>info</mat-icon>
+                  <span>Modified this session</span>
+                </div>
+              }
+            </div>
+          } @else {
+            <div class="empty-flags-box">
+              <div class="icon-circle"><mat-icon>not_interested</mat-icon></div>
+              <p>No flags specified.</p>
+              <a (click)="openFlagsDialog()">Click here to use example args (Optional)</a>
+            </div>
+          }
+        </div>
+      </div>
+    }
+  </mat-dialog-content>
+  <ng-template #actionsTemplate>
+    <div class="footer-actions">
+      <button class="tertiary-button" [mat-dialog-close]="'cancel'">Cancel</button>
+      @if (currentStep() === 2) {
+        <button class="secondary-button" (click)="back()" [disabled]="isDeploying()">Back</button>
+        <button class="primary-button" (click)="deploy()" [disabled]="isDeploying()">
+          @if (isDeploying()) {
+            <mat-spinner diameter="20" class="mr-2"></mat-spinner>
+            Deploying...
+          } @else {
+            <ng-container>
+              <mat-icon class="mr-2">rocket_launch</mat-icon>
+              Deploy
+            </ng-container>
+          }
+        </button>
+      } @else {
+        <button class="primary-button" [disabled]="!selectedVersion()" (click)="proceed()">
+          {{ selectedVersion() ? 'Continue' : 'Select a version to proceed' }}
+          @if (selectedVersion()) {
+            <mat-icon>arrow_forward</mat-icon>
+          }
+        </button>
+      }
+    </div>
+  </ng-template>
+</app-dialog>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.scss b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.scss
new file mode 100644
index 0000000000..38f52d49e2
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.scss
@@ -0,0 +1,612 @@
+@use '@angular/material' as mat;
+@use  '../../../../../shared/styles/common.scss' as common;
+@use '../../../../../shared/styles/typography.scss' as typography;
+
+:host {
+  @include mat.table-overrides((
+    header-container-height: 3rem,
+  ));
+}
+
+.dialog-content {
+  @include common.shared-scrollbar-style();
+  flex-grow: 1;
+  overflow-y: auto;
+  padding: 1.5rem;
+  background-color: #f8fafc;
+}
+
+.info-alert {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  background-color: #eff6ff;
+  color: #1d4ed8;
+  padding: 0.5rem 1rem;
+  border-radius: 0.5rem;
+  border: 1px solid #dbeafe;
+  margin-bottom: 1rem;
+
+  span {
+    font-weight: 500;
+    font-size: 0.875rem;
+    line-height: 1.25rem;
+  }
+}
+
+.content-splitter {
+  display: flex;
+  align-items: stretch;
+  overflow: hidden;
+  height: 500px;
+}
+
+.versions-panel {
+  flex-grow: 1;
+  overflow-y: auto;
+  border: 1px solid #e2e8f0;
+  border-radius: 0.75rem;
+  background-color: white;
+  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
+
+  .versions-table {
+    width: 100%;
+    border-collapse: collapse;
+    text-align: left;
+
+    th {
+      background-color: #f8fafc;
+      padding: 0.75rem 1rem;
+      font-size: 0.75rem;
+      font-weight: 600;
+      color: #64748b;
+      border-bottom: 1px solid #e2e8f0;
+      position: sticky;
+      top: 0;
+      z-index: 10;
+    }
+
+    td {
+      padding: 0.75rem 1rem;
+      border-bottom: 1px solid #f1f5f9;
+      font-size: 0.875rem;
+    }
+
+    .version-row {
+      cursor: pointer;
+      transition: background-color 0.2s;
+
+      &:hover {
+        background-color: #f8fafc;
+      }
+
+      &.selected {
+        background-color: #eff6ff;
+
+        .version-label {
+          color: #1e40af;
+        }
+      }
+    }
+
+    .version-label {
+      font-weight: 700;
+      color: #0f172a;
+    }
+
+    .version-name {
+      font-size: 0.75rem;
+      color: #94a3b8;
+      margin-top: 0.125rem;
+    }
+
+    .status-badge {
+      font-size: 0.75rem;
+      font-weight: 700;
+      padding: 0.125rem 0.5rem;
+      border-radius: 9999px;
+      border: 1px solid transparent;
+
+      &.latest {
+        background-color: #dcfce7;
+        color: #15803d;
+        border-color: #bbf7d0;
+      }
+
+      &.current {
+        background-color: #dbeafe;
+        color: #1d4ed8;
+        border-color: #bfdbfe;
+      }
+    }
+
+    .row-actions {
+      display: flex;
+      justify-content: flex-end;
+      align-items: center;
+      gap: 0.5rem;
+
+      button[mat-icon-button] {
+        color: #2563eb;
+        opacity: 1;
+      }
+
+      button[mat-flat-button] {
+        background-color: #2563eb;
+        color: white;
+      }
+    }
+  }
+}
+
+.manifest-panel {
+  width: 0;
+  opacity: 0;
+  border: 1px solid #e2e8f0;
+  border-radius: 0.75rem;
+  background-color: white;
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+  letter-spacing: normal;
+
+  &.open {
+    transform: translateX(0);
+    width: 400px;
+    margin-left: 1rem;
+    opacity: 1;
+  }
+
+  .manifest-header {
+    padding: 0 0 0 1rem;
+    background-color: #f8fafc;
+    border-bottom: 1px solid #e2e8f0;
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    font-size: 0.75rem;
+    font-weight: 700;
+    color: #334155;
+    flex-shrink: 0;
+  }
+
+  .manifest-tabs {
+    display: flex;
+    border-bottom: 1px solid #e2e8f0;
+    flex-shrink: 0;
+
+    .tab-btn {
+      flex-grow: 1;
+      padding: 0.5rem;
+      font-size: 0.75rem;
+      font-weight: 700;
+      color: #94a3b8;
+      border: none;
+      border-bottom: 2px solid transparent;
+      background: none;
+      cursor: pointer;
+      transition: all 0.2s;
+
+      &:hover {
+        color: #64748b;
+      }
+
+      &.active {
+        color: #1d4ed8;
+        border-bottom-color: #2563eb;
+        background-color: #eff6ff;
+      }
+    }
+  }
+
+  .manifest-content {
+    flex-grow: 1;
+    overflow-y: auto;
+    padding: 1rem;
+  }
+
+  .metadata-content {
+    display: flex;
+    flex-direction: column;
+    gap: 1rem;
+
+    .detail-item {
+      display: flex;
+      gap: 0.75rem;
+      align-items: flex-start;
+
+      mat-icon {
+        color: #2563eb;
+        font-size: 1.25rem;
+        width: 1.25rem;
+        height: 1.25rem;
+      }
+
+      .label {
+        font-size: 0.75rem;
+        font-weight: 700;
+        color: #94a3b8;
+      }
+
+      .value {
+        font-size: 0.875rem;
+        font-weight: 700;
+        color: #334155;
+      }
+    }
+
+    .changelist-section {
+      margin-top: 0.5rem;
+      border-top: 1px solid #f1f5f9;
+      padding-top: 0.75rem;
+
+      .section-title {
+        font-size: 0.75rem;
+        font-weight: 700;
+        color: #94a3b8;
+        margin-bottom: 0.5rem;
+      }
+
+      ul {
+        list-style: none;
+        padding: 0;
+        margin: 0;
+        display: flex;
+        flex-direction: column;
+        gap: 0.5rem;
+
+        li {
+          font-size: 0.75rem;
+          line-height: 1.4;
+          color: #334155;
+        }
+
+        .cl-number {
+          font-family: monospace;
+          font-weight: 700;
+          color: #2563eb;
+        }
+
+        .bug-number {
+          color: #94a3b8;
+        }
+      }
+    }
+  }
+
+  .files-content {
+    display: flex;
+    flex-direction: column;
+    gap: 0.75rem;
+
+    .file-item {
+      padding: 0.75rem;
+      background-color: #f8fafc;
+      border: 1px solid #e2e8f0;
+      border-radius: 0.5rem;
+
+      .file-key {
+        font-size: 0.75rem;
+        font-family: monospace;
+        font-weight: 700;
+        color: #2563eb;
+        margin-bottom: 0.25rem;
+      }
+
+      .file-value {
+        font-size: 0.75rem;
+        font-family: monospace;
+        color: #475569;
+        word-break: break-all;
+
+        &.not-set {
+          color: #d1d5db;
+          font-style: italic;
+        }
+      }
+    }
+  }
+
+  .commands-content {
+    .section-title {
+      font-size: 0.75rem;
+      font-weight: 700;
+      color: #94a3b8;
+    }
+
+    .command-name {
+      font-size: 0.75rem;
+      font-weight: 700;
+      color: #6b7280;
+      margin-bottom: 0.25rem;
+    }
+
+    .command-block {
+      display: block;
+      background-color: #0f172a;
+      color: #93c5fd;
+      padding: 0.5rem;
+      border-radius: 0.25rem;
+      font-size: 0.75rem;
+      font-family: monospace;
+      word-break: break-all;
+      margin-bottom: 0.5rem;
+      border-left: 2px solid #2563eb;
+
+      &.async {
+        border-left-color: #8b5cf6;
+        color: #c7d2fe;
+      }
+    }
+  }
+
+  .empty-text {
+    font-size: 0.875rem;
+    font-weight: 500;
+    color: #9ca3af;
+    text-align: center;
+  }
+}
+
+.step-2-container {
+  max-width: 600px;
+  margin: 0 auto;
+  padding-top: 1rem;
+  letter-spacing: normal;
+
+  .step-2-header {
+    display: flex;
+    gap: 1rem;
+    align-items: center;
+    margin-bottom: 2rem;
+
+    .header-icon {
+      width: 3rem;
+      height: 3rem;
+      background-color: #eff6ff;
+      color: #2563eb;
+      border-radius: 9999px;
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      border: 1px solid #dbeafe;
+
+      mat-icon {
+        font-size: 1.5rem;
+        width: 1.5rem;
+        height: 1.5rem;
+      }
+    }
+
+    h3 {
+      font-size: 1.5rem;
+      font-weight: 700;
+      color: #0f172a;
+      margin: 0;
+    }
+
+    p {
+      font-size: 0.875rem;
+      color: #64748b;
+      margin: 0.25rem 0 0 0;
+    }
+  }
+}
+
+
+.version-summary-card {
+  background-color: white;
+  border: 1px solid #e2e8f0;
+  border-radius: 1rem;
+  padding: 1rem;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: 2rem;
+  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
+
+  .left-section {
+    display: flex;
+    gap: 1rem;
+    align-items: center;
+  }
+
+  .icon-bg {
+    width: 2.5rem;
+    height: 2.5rem;
+    background-color: #f1f5f9;
+    color: #94a3b8;
+    border-radius: 0.5rem;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+  }
+
+  .label {
+    font-size: 0.625rem;
+    font-weight: 700;
+    color: #9ca3af;
+    letter-spacing: normal;
+  }
+
+  .value {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    margin-top: 0.125rem;
+
+    .version-str {
+      font-size: 1.25rem;
+      font-family: monospace;
+      font-weight: 700;
+      color: #0f172a;
+    }
+  }
+
+  .right-section {
+    text-align: right;
+
+    .value {
+      justify-content: flex-end;
+      font-size: 0.875rem;
+      font-weight: 600;
+      color: #475569;
+    }
+  }
+}
+
+.flags-section {
+  .section-header {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    margin-bottom: 0.75rem;
+  }
+
+
+
+  .title-section {
+    display: flex;
+    gap: 0.5rem;
+    align-items: center;
+  }
+
+  .header-title {
+    font-size: 0.75rem;
+    line-height: 1rem;
+    font-weight: 700;
+    color: #374151;
+  }
+
+  .optional-badge {
+    font-size: 0.625rem;
+    color: #9ca3af;
+    height: 21px;
+    padding: 0 0.375rem;
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    border-radius: 0.25rem;
+    border: 1px solid #e2e8f0;
+    background-color: #f9fafb;
+    box-sizing: border-box;
+    font-weight: 500;
+  }
+
+  .add-flags-button {
+    color: #2563eb;
+    font-size: 0.75rem;
+    line-height: 1rem;
+    letter-spacing: normal;
+    font-weight: 700;
+  }
+
+  .flags-code-block {
+    background-color: #f8fafc;
+    border: 1px solid #e2e8f0;
+    border-radius: 0.75rem;
+    padding: 1rem;
+    font-family: monospace;
+    font-size: 0.75rem;
+    color: #475569;
+    word-break: break-all;
+    max-height: 160px;
+    overflow-y: auto;
+
+    .modified-label {
+      display: flex;
+      align-items: center;
+      gap: 0.25rem;
+      color: #d97706;
+      font-weight: 500;
+      font-size: 0.685rem;
+      font-family: typography.$labconsole-font;
+      margin-top: 0.5rem;
+      border-top: 1px solid #e2e8f066;
+      padding-top: 0.5rem;
+
+      mat-icon {
+        font-size: 0.685rem;
+        height: 0.685rem;
+        width: 0.685rem;
+        color: #d97706;
+      }
+    }
+  }
+
+  .empty-flags-box {
+    padding: 2rem;
+    border: 2px dashed #e2e8f0;
+    border-radius: 1rem;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    text-align: center;
+    cursor: pointer;
+    transition: border-color 0.2s;
+
+    &:hover {
+      border-color: #cbd5e1;
+    }
+
+    .icon-circle {
+      width: 2.5rem;
+      height: 2.5rem;
+      background-color: #f8fafc;
+      color: #cbd5e1;
+      border-radius: 9999px;
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      margin-bottom: 0.75rem;
+    }
+
+    p {
+      font-size: 0.875rem;
+      font-weight: 500;
+      color: #94a3b8;
+      margin: 0;
+    }
+
+    a {
+      color: #3b82f6;
+      font-weight: 700;
+      font-size: 0.75rem;
+      text-decoration: none;
+    }
+  }
+}
+
+.footer-actions {
+  display: flex;
+  gap: 0.75rem;
+  align-items: center;
+
+  .primary-button {
+    @include common.shared-button('primary');
+
+    mat-icon {
+      height: 1rem;
+      width: 1rem;
+      font-size: 1rem;
+      margin-left: 0.25rem;
+    }
+  }
+
+  .secondary-button {
+    @include common.shared-button('secondary');
+  }
+
+  .tertiary-button {
+    @include common.shared-button('tertiary');
+    border-color: transparent;
+  }
+
+  .mr-2 {
+    margin-right: 0.5rem;
+  }
+}
+
+
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ts b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ts
new file mode 100644
index 0000000000..5a24e9d019
--- /dev/null
+++ b/src/devtools/mobileharness/fe/v6/angular/app/features/host_detail/components/host_overview/release_dialog/release_dialog.ts
@@ -0,0 +1,156 @@
+import {CommonModule} from '@angular/common';
+import {
+  ChangeDetectionStrategy,
+  Component,
+  computed,
+  inject,
+  OnInit,
+  signal,
+  WritableSignal,
+} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {MatButtonModule} from '@angular/material/button';
+import {
+  MAT_DIALOG_DATA,
+  MatDialog,
+  MatDialogModule,
+} from '@angular/material/dialog';
+import {MatFormFieldModule} from '@angular/material/form-field';
+import {MatIconModule} from '@angular/material/icon';
+import {MatInputModule} from '@angular/material/input';
+import {MatProgressSpinnerModule} from '@angular/material/progress-spinner';
+import {MatTableModule} from '@angular/material/table';
+
+import {DeployableVersion} from 'app/core/models/host_action';
+import {FlagsDialog} from 'app/features/host_detail/components/host_overview/flags_dialog/flags_dialog';
+import {Dialog} from 'app/shared/components/config_common/dialog/dialog';
+import {SnackBarService} from 'app/shared/services/snackbar_service';
+
+/**
+ * Data passed to the ReleaseDialog component.
+ */
+export interface ReleaseDialogData {
+  hostName: string;
+  releaseConfigs?: DeployableVersion[];
+  passThroughFlags: WritableSignal<string>;
+}
+
+/**
+ * Component for displaying and managing host releases.
+ */
+@Component({
+  selector: 'app-release-dialog',
+  standalone: true,
+  templateUrl: './release_dialog.ng.html',
+  styleUrl: './release_dialog.scss',
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  imports: [
+    Dialog,
+    MatTableModule,
+    CommonModule,
+    FormsModule,
+    MatDialogModule,
+    MatFormFieldModule,
+    MatIconModule,
+    MatInputModule,
+    MatButtonModule,
+    MatProgressSpinnerModule,
+  ],
+})
+export class ReleaseDialog implements OnInit {
+  readonly data: ReleaseDialogData = inject(MAT_DIALOG_DATA);
+  private readonly snackBar = inject(SnackBarService);
+  private readonly dialog = inject(MatDialog);
+
+  displayedColumns: string[] = ['version', 'buildTime', 'status', 'actions'];
+
+  readonly currentStep = signal<number>(1);
+  readonly selectedVersion = signal<DeployableVersion | null>(null);
+
+  readonly hasSyncCommands = computed(() => {
+    return !!this.selectedVersion()?.releaseDetails?.syncCommands?.length;
+  });
+
+  readonly hasAsyncCommands = computed(() => {
+    return !!this.selectedVersion()?.releaseDetails?.asyncCommands?.length;
+  });
+
+  readonly hasCommands = computed(() => {
+    return this.hasSyncCommands() || this.hasAsyncCommands();
+  });
+  readonly currentTab = signal<string>('metadata');
+  readonly tempFlags = signal<string>('');
+  readonly flagsModifiedThisSession = signal<boolean>(false);
+  readonly showDetails = signal<boolean>(false);
+  readonly isDeploying = signal<boolean>(false);
+
+  availableVersions: DeployableVersion[] = [];
+
+  ngOnInit() {
+    this.availableVersions = this.data.releaseConfigs || [];
+    this.tempFlags.set(this.data.passThroughFlags());
+  }
+
+  selectVersion(version: DeployableVersion) {
+    this.selectedVersion.set(version);
+  }
+
+  viewDetails(version: DeployableVersion) {
+    const current = this.selectedVersion();
+    if (current?.version === version.version && this.showDetails()) {
+      this.showDetails.set(false);
+    } else {
+      this.selectedVersion.set(version);
+      this.showDetails.set(true);
+    }
+  }
+
+  switchTab(tab: string) {
+    this.currentTab.set(tab);
+  }
+
+  proceed() {
+    if (this.selectedVersion()) {
+      this.currentStep.set(2);
+    }
+  }
+
+  back() {
+    this.currentStep.set(1);
+  }
+
+  deploy() {
+    this.isDeploying.set(true);
+    // Simulate deployment delay
+    setTimeout(() => {
+      this.isDeploying.set(false);
+      this.snackBar.showSuccess(
+        `Deployed ${this.selectedVersion()?.version} successfully`,
+      );
+    }, 1500);
+  }
+
+  openFlagsDialog() {
+    const dialogRef = this.dialog.open(FlagsDialog, {
+      data: {
+        hostName: this.data.hostName,
+        currentFlags: this.tempFlags(),
+      },
+      width: '72rem',
+      maxHeight: '90vh',
+      autoFocus: false,
+    });
+
+    dialogRef.afterClosed().subscribe((result) => {
+      // Only update if the result is a string and not the explicit 'close' signal.
+      if (typeof result === 'string' && result !== 'close') {
+        if (result !== this.tempFlags()) {
+          this.flagsModifiedThisSession.set(true);
+          this.snackBar.showSuccess('Pass-through flags updated successfully');
+        }
+        this.data.passThroughFlags.set(result);
+        this.tempFlags.set(result);
+      }
+    });
+  }
+}
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ng.html
index e7edd4bc42..8ef9f9de52 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ng.html
+++ b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ng.html
@@ -1,6 +1,7 @@
 <div class="config-modal-container">
-  <div class="config-modal-card" [style.max-width]="width" [style.height]="height">
+  <div class="config-modal-card" [style.max-width]="width" [style.height]="height" [style.max-height]="maxHeight">
     <header class="config-header">
+      <ng-content select="[header-prefix]"></ng-content>
       <div class="header-title-container">
         <h2 class="config-title">{{ title }}</h2>
         <p class="config-subtitle" [innerHTML]="subtitle | safeHtmlPipe"></p>
@@ -9,7 +10,7 @@ <h2 class="config-title">{{ title }}</h2>
         <div class="header-menu">
           <ng-content select="[header-button]"></ng-content>
         </div>
-        <button mat-icon-button mat-dialog-close class="close-button">
+        <button mat-icon-button [mat-dialog-close] class="close-button">
           <mat-icon>close</mat-icon>
         </button>
       </div>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ts b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ts
index 4e855d226b..ab87d3faae 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/config_common/dialog/dialog.ts
@@ -38,6 +38,7 @@ import {Footer} from '../footer/footer';
 export class Dialog implements OnInit {
   @Input() width = '48rem';
   @Input() height = '';
+  @Input() maxHeight = '';
 
   @Input() title = '';
   @Input() subtitle = '';
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ng.html b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ng.html
index 4353cc6e01..65df80a570 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ng.html
+++ b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ng.html
@@ -1,7 +1,7 @@
 <div class="confirm-dialog-container">
   <div class="confirm-dialog-header">
-    <mat-icon class="sub-modal-icon" [class]="iconUI.iconColorClass">
-      {{ iconUI.icon }}
+    <mat-icon class="sub-modal-icon" [class]="iconUI().iconColorClass">
+      {{ iconUI().icon }}
     </mat-icon>
     <h3 class="text-gray-800">{{ data.title }}</h3>
   </div>
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.scss b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.scss
index 4fb807eda0..6383568b0b 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.scss
+++ b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.scss
@@ -7,7 +7,7 @@
 
   @include mat.dialog-overrides((
     container-shape: .5rem,
-    container-max-width: 35rem,
+    container-max-width: fit-content,
   ));
 }
 
@@ -431,7 +431,7 @@
 }
 
 .info-icon {
-  color: #1976d2;
+  color: #2563eb;
 }
 
 .warning-icon {
diff --git a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ts b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ts
index 89ea6f64ec..8589658eb4 100644
--- a/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ts
+++ b/src/devtools/mobileharness/fe/v6/angular/app/shared/components/confirm_dialog/confirm_dialog.ts
@@ -2,6 +2,7 @@ import {CommonModule} from '@angular/common';
 import {
   ChangeDetectionStrategy,
   Component,
+  computed,
   inject,
   OnInit,
   signal,
@@ -46,6 +47,7 @@ export class ConfirmDialog implements OnInit {
     primaryButtonIcon?: string;
     secondaryButtonLabel?: string;
     onConfirm?: () => Observable<void>;
+    customIcon?: string;
   }>(MAT_DIALOG_DATA);
 
   private readonly dialogRef = inject(MatDialogRef<ConfirmDialog>);
@@ -78,8 +80,17 @@ export class ConfirmDialog implements OnInit {
     }
   }
 
-  get iconUI() {
-    switch (this.data.type) {
+  readonly iconUI = computed(() => {
+    const type = this.data.type || 'info';
+    if (this.data.customIcon) {
+      return {
+        icon: this.data.customIcon,
+        iconColorClass: `${type}-icon`,
+        iconBgColorClass: `bg-${type === 'error' ? 'red' : type === 'warning' ? 'yellow' : type === 'success' ? 'green' : 'gray'}-100`,
+      };
+    }
+
+    switch (type) {
       case 'info':
         return {
           icon: 'info',
@@ -106,5 +117,5 @@ export class ConfirmDialog implements OnInit {
           iconBgColorClass: 'bg-red-100',
         };
     }
-  }
+  });
 }
diff --git a/src/devtools/mobileharness/fe/v6/service/proto/host/host_resources.proto b/src/devtools/mobileharness/fe/v6/service/proto/host/host_resources.proto
index 870bcb1fd0..7bc27301f7 100644
--- a/src/devtools/mobileharness/fe/v6/service/proto/host/host_resources.proto
+++ b/src/devtools/mobileharness/fe/v6/service/proto/host/host_resources.proto
@@ -111,20 +111,53 @@ message PopularFlag {
   string cmd = 3;
 }
 
-// A preset configuration for pass-through flags.
-message FlagPreset {
-  string label = 1;
-  string value = 2;
-  string description = 3;
+message ChangeRecord {
+  int64 cl = 1;
+  string author = 2;
+  string text = 3;
+  repeated int32 bugs = 4;
+}
+
+message BugRecord {
+  int32 bug = 1;
+  string text = 2;
 }
 
-// Configuration for a specific Lab Server release.
-message HostReleaseConfig {
+message ChangeLogGroup {
   string name = 1;
-  string version = 2;
-  ReleasePort port = 3;
-  repeated string sync_cmd = 4;
-  repeated string async_cmd = 5;
+  message Item {
+    oneof type {
+      ChangeRecord change = 1;
+      BugRecord bug = 2;
+    }
+  }
+  repeated Item items = 2;
+}
+
+message FileRecord {
+  string name = 1;
+  string path = 2;
+}
+
+message CommandRecord {
+  string name = 1;
+  string command = 2;
+}
+
+message ReleaseDetails {
+  repeated ChangeLogGroup change_logs = 1;
+  repeated FileRecord files = 2;
+  repeated CommandRecord sync_commands = 3;
+  repeated CommandRecord async_commands = 4;
+}
+
+message DeployableVersion {
+  string name = 1;        // Release name
+  string version = 2;     // Version string (e.g. "v4.358.0")
+  string status = 3;      // "Latest", "Current", or empty
+  string build_time = 4;  // Build timestamp
+  repeated ReleasePort ports = 5;
+  ReleaseDetails release_details = 6;
 }
 
 // Port configuration for a release.
diff --git a/src/devtools/mobileharness/fe/v6/service/proto/host/host_service.proto b/src/devtools/mobileharness/fe/v6/service/proto/host/host_service.proto
index 68be9ac7e5..1f52f94039 100644
--- a/src/devtools/mobileharness/fe/v6/service/proto/host/host_service.proto
+++ b/src/devtools/mobileharness/fe/v6/service/proto/host/host_service.proto
@@ -76,10 +76,10 @@ service HostService {
   }
 
   // Retrieves release configurations for a host.
-  rpc GetReleaseConfigs(GetReleaseConfigsRequest)
-      returns (GetReleaseConfigsResponse) {
+  rpc PreflightLabServerRelease(PreflightLabServerReleaseRequest)
+      returns (PreflightLabServerReleaseResponse) {
     option (google.api.http) = {
-      get: "/v6/hosts/{host_name}/release-configs"
+      get: "/v6/hosts/{host_name}/preflightLabServerRelease"
     };
   }
 
@@ -229,17 +229,28 @@ message UpdatePassThroughFlagsRequest {
 // Response message for UpdatePassThroughFlags.
 message UpdatePassThroughFlagsResponse {}
 
-// Request message for GetReleaseConfigs.
-message GetReleaseConfigsRequest {
+// Request message for PreflightLabServerRelease.
+message PreflightLabServerReleaseRequest {
   string host_name = 1;
 
   // The universe of the host.
   string universe = 2;
 }
 
-// Response message for GetReleaseConfigs.
-message GetReleaseConfigsResponse {
-  repeated HostReleaseConfig configs = 1;
+// Response message for PreflightLabServerRelease.
+message PreflightLabServerReleaseResponse {
+  // No deploy permission.
+  message PermissionDenied {}
+
+  // All checks passed. Here are the available versions to deploy.
+  message ReleaseReady {
+    repeated DeployableVersion versions = 1;
+  }
+
+  oneof result {
+    PermissionDenied permission_denied = 1;
+    ReleaseReady ready = 2;
+  }
 }
 
 // Request message for DecommissionMissingDevices.
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceGrpcImpl.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceGrpcImpl.java
index fd31b2ae74..38160425e2 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceGrpcImpl.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceGrpcImpl.java
@@ -32,11 +32,11 @@
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetHostOverviewRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsRequest;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostHeaderInfo;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostOverviewPageData;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostServiceGrpc;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesRequest;
@@ -140,16 +140,16 @@ public void updatePassThroughFlags(
   }
 
   @Override
-  public void getReleaseConfigs(
-      GetReleaseConfigsRequest request,
-      StreamObserver<GetReleaseConfigsResponse> responseObserver) {
+  public void preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request,
+      StreamObserver<PreflightLabServerReleaseResponse> responseObserver) {
     GrpcServiceUtil.invokeAsync(
         request,
         responseObserver,
-        logic::getReleaseConfigs,
+        req -> logic.preflightLabServerRelease(req, Optional.empty()),
         executor,
         HostServiceGrpc.getServiceDescriptor(),
-        HostServiceGrpc.getGetReleaseConfigsMethod());
+        HostServiceGrpc.getPreflightLabServerReleaseMethod());
   }
 
   @Override
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogic.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogic.java
index f18afc9bce..62383d80ea 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogic.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogic.java
@@ -31,10 +31,10 @@
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetHostOverviewRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsRequest;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostHeaderInfo;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostOverviewPageData;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesRequest;
@@ -65,7 +65,8 @@ ListenableFuture<GetHostDeviceSummariesResponse> getHostDeviceSummaries(
   ListenableFuture<UpdatePassThroughFlagsResponse> updatePassThroughFlags(
       UpdatePassThroughFlagsRequest request);
 
-  ListenableFuture<GetReleaseConfigsResponse> getReleaseConfigs(GetReleaseConfigsRequest request);
+  ListenableFuture<PreflightLabServerReleaseResponse> preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request, Optional<String> username);
 
   ListenableFuture<DecommissionMissingDevicesResponse> decommissionMissingDevices(
       DecommissionMissingDevicesRequest request);
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImpl.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImpl.java
index a50eba6fe0..d8e7b62f01 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImpl.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImpl.java
@@ -25,6 +25,8 @@
 import com.google.devtools.mobileharness.fe.v6.service.host.handlers.GetHostDeviceSummariesHandler;
 import com.google.devtools.mobileharness.fe.v6.service.host.handlers.GetHostHeaderInfoHandler;
 import com.google.devtools.mobileharness.fe.v6.service.host.handlers.GetHostOverviewHandler;
+import com.google.devtools.mobileharness.fe.v6.service.host.handlers.GetPopularFlagsHandler;
+import com.google.devtools.mobileharness.fe.v6.service.host.handlers.PreflightLabServerReleaseHandler;
 import com.google.devtools.mobileharness.fe.v6.service.host.handlers.RemoteControlDevicesHandler;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.CheckRemoteControlEligibilityRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.CheckRemoteControlEligibilityResponse;
@@ -40,10 +42,10 @@
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetHostOverviewRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsRequest;
-import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetReleaseConfigsResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostHeaderInfo;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostOverviewPageData;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.ReleaseLabServerResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesRequest;
@@ -72,6 +74,8 @@ public final class HostServiceLogicImpl implements HostServiceLogic {
   private final RemoteControlDevicesHandler remoteControlDevicesHandler;
   private final GetHostHeaderInfoHandler getHostHeaderInfoHandler;
   private final DecommissionMissingDevicesHandler decommissionMissingDevicesHandler;
+  private final PreflightLabServerReleaseHandler preflightLabServerReleaseHandler;
+  private final GetPopularFlagsHandler getPopularFlagsHandler;
   private final UniverseFactory universeFactory;
 
   @Inject
@@ -82,6 +86,8 @@ public final class HostServiceLogicImpl implements HostServiceLogic {
       RemoteControlDevicesHandler remoteControlDevicesHandler,
       GetHostHeaderInfoHandler getHostHeaderInfoHandler,
       DecommissionMissingDevicesHandler decommissionMissingDevicesHandler,
+      PreflightLabServerReleaseHandler preflightLabServerReleaseHandler,
+      GetPopularFlagsHandler getPopularFlagsHandler,
       UniverseFactory universeFactory) {
     this.getHostOverviewHandler = getHostOverviewHandler;
     this.getHostDeviceSummariesHandler = getHostDeviceSummariesHandler;
@@ -89,6 +95,8 @@ public final class HostServiceLogicImpl implements HostServiceLogic {
     this.remoteControlDevicesHandler = remoteControlDevicesHandler;
     this.getHostHeaderInfoHandler = getHostHeaderInfoHandler;
     this.decommissionMissingDevicesHandler = decommissionMissingDevicesHandler;
+    this.preflightLabServerReleaseHandler = preflightLabServerReleaseHandler;
+    this.getPopularFlagsHandler = getPopularFlagsHandler;
     this.universeFactory = universeFactory;
   }
 
@@ -138,11 +146,13 @@ public ListenableFuture<GetHostDebugInfoResponse> getHostDebugInfo(
 
   @Override
   public ListenableFuture<GetPopularFlagsResponse> getPopularFlags(GetPopularFlagsRequest request) {
-    // TODO: Use the universe parameter.
-    @SuppressWarnings("unused")
-    String universe = request.getUniverse();
-    // TODO: Implement this method.
-    return immediateFuture(GetPopularFlagsResponse.getDefaultInstance());
+    UniverseScope universe;
+    try {
+      universe = universeFactory.create(request.getUniverse());
+    } catch (IllegalArgumentException e) {
+      return immediateFailedFuture(e);
+    }
+    return getPopularFlagsHandler.getPopularFlags(request, universe);
   }
 
   @Override
@@ -156,13 +166,15 @@ public ListenableFuture<UpdatePassThroughFlagsResponse> updatePassThroughFlags(
   }
 
   @Override
-  public ListenableFuture<GetReleaseConfigsResponse> getReleaseConfigs(
-      GetReleaseConfigsRequest request) {
-    // TODO: Use the universe parameter.
-    @SuppressWarnings("unused")
-    String universe = request.getUniverse();
-    // TODO: Implement this method.
-    return immediateFuture(GetReleaseConfigsResponse.getDefaultInstance());
+  public ListenableFuture<PreflightLabServerReleaseResponse> preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request, Optional<String> username) {
+    UniverseScope universe;
+    try {
+      universe = universeFactory.create(request.getUniverse());
+    } catch (IllegalArgumentException e) {
+      return immediateFailedFuture(e);
+    }
+    return preflightLabServerReleaseHandler.preflightLabServerRelease(request, universe, username);
   }
 
   @Override
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/BUILD b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/BUILD
similarity index 85%
rename from src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/BUILD
rename to src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/BUILD
index 61fff8b0b3..960de7cd90 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/BUILD
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/BUILD
@@ -21,11 +21,14 @@ package(
 )
 
 java_library(
-    name = "builder",
+    name = "builders",
     srcs = glob(["*.java"]),
     deps = [
         "//src/devtools/mobileharness/api/query/proto:lab_query_java_proto",
         "//src/devtools/mobileharness/fe/v6/service/proto/host:host_resources_java_proto",
         "//src/devtools/mobileharness/fe/v6/service/proto/host:host_service_java_proto",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/util",
+        "@maven//:com_google_guava_guava",
+        "@maven//:javax_inject_jsr330_api",
     ],
 )
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpPopularFlagsBuilder.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpPopularFlagsBuilder.java
new file mode 100644
index 0000000000..9bdcd672b4
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpPopularFlagsBuilder.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.builders;
+
+import static com.google.common.util.concurrent.Futures.immediateFuture;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import javax.inject.Singleton;
+
+/** No-op implementation of {@link PopularFlagsBuilder} returning empty flags. */
+@Singleton
+public final class NoOpPopularFlagsBuilder implements PopularFlagsBuilder {
+
+  @Override
+  public ListenableFuture<GetPopularFlagsResponse> getPopularFlags(
+      GetPopularFlagsRequest request, UniverseScope universe) {
+    return immediateFuture(GetPopularFlagsResponse.getDefaultInstance());
+  }
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/NoOpRemoteControlUrlBuilder.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpRemoteControlUrlBuilder.java
similarity index 99%
rename from src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/NoOpRemoteControlUrlBuilder.java
rename to src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpRemoteControlUrlBuilder.java
index 88c08330d0..1670013bc7 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/NoOpRemoteControlUrlBuilder.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/NoOpRemoteControlUrlBuilder.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package com.google.devtools.mobileharness.fe.v6.service.host.builder;
+package com.google.devtools.mobileharness.fe.v6.service.host.builders;
 
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.DeviceInfo;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDeviceConfig;
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/PopularFlagsBuilder.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/PopularFlagsBuilder.java
new file mode 100644
index 0000000000..e73bfaff7b
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/PopularFlagsBuilder.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.builders;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+
+/** Builder for popular pass-through flags. */
+public interface PopularFlagsBuilder {
+
+  /** Builds popular pass-through flags for the host. */
+  ListenableFuture<GetPopularFlagsResponse> getPopularFlags(
+      GetPopularFlagsRequest request, UniverseScope universe);
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/RemoteControlUrlBuilder.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/RemoteControlUrlBuilder.java
similarity index 99%
rename from src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/RemoteControlUrlBuilder.java
rename to src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/RemoteControlUrlBuilder.java
index d3899c437c..b499036da2 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder/RemoteControlUrlBuilder.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders/RemoteControlUrlBuilder.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package com.google.devtools.mobileharness.fe.v6.service.host.builder;
+package com.google.devtools.mobileharness.fe.v6.service.host.builders;
 
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.DeviceInfo;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDeviceConfig;
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
index 2051443241..e5f8cc3254 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
@@ -34,7 +34,7 @@ java_library(
         "//src/devtools/mobileharness/infra/master/rpc/proto:lab_sync_service_java_proto",
         "//src/devtools/mobileharness/shared/labinfo/proto:lab_info_service_java_proto",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/device/handlers",
-        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/provider",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/util:daemon_statuses",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/util:host_connectivity_statuses",
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/GetPopularFlagsHandler.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/GetPopularFlagsHandler.java
new file mode 100644
index 0000000000..f0f85d8b6e
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/GetPopularFlagsHandler.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.handlers;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.PopularFlagsBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+/** Handler for the GetPopularFlags RPC. */
+@Singleton
+public final class GetPopularFlagsHandler {
+
+  private final PopularFlagsBuilder popularFlagsBuilder;
+
+  @Inject
+  GetPopularFlagsHandler(PopularFlagsBuilder popularFlagsBuilder) {
+    this.popularFlagsBuilder = popularFlagsBuilder;
+  }
+
+  public ListenableFuture<GetPopularFlagsResponse> getPopularFlags(
+      GetPopularFlagsRequest request, UniverseScope universe) {
+    return popularFlagsBuilder.getPopularFlags(request, universe);
+  }
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPopularFlagsBuilder.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPopularFlagsBuilder.java
new file mode 100644
index 0000000000..d840d55938
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPopularFlagsBuilder.java
@@ -0,0 +1,15 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPreflightLabServerReleaseActionHelper.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPreflightLabServerReleaseActionHelper.java
new file mode 100644
index 0000000000..6672a17ee2
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/NoOpPreflightLabServerReleaseActionHelper.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.handlers;
+
+import static com.google.common.util.concurrent.Futures.immediateFailedFuture;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import java.util.Optional;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+/** No-op implementation of {@link PreflightLabServerReleaseActionHelper}. */
+@Singleton
+public final class NoOpPreflightLabServerReleaseActionHelper
+    implements PreflightLabServerReleaseActionHelper {
+
+  @Inject
+  NoOpPreflightLabServerReleaseActionHelper() {}
+
+  @Override
+  public ListenableFuture<PreflightLabServerReleaseResponse> preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request, UniverseScope universe, Optional<String> username) {
+    return immediateFailedFuture(
+        new UnsupportedOperationException(
+            "Preflight lab server release is not supported in the current environment."));
+  }
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseActionHelper.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseActionHelper.java
new file mode 100644
index 0000000000..7c70fa1fe4
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseActionHelper.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.handlers;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import java.util.Optional;
+
+/** Helper for {@link PreflightLabServerReleaseHandler}. */
+public interface PreflightLabServerReleaseActionHelper {
+
+  ListenableFuture<PreflightLabServerReleaseResponse> preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request, UniverseScope universe, Optional<String> username);
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandler.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandler.java
new file mode 100644
index 0000000000..e1445c2d47
--- /dev/null
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandler.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.handlers;
+
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import java.util.Optional;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+/** Handler for the PreflightLabServerRelease RPC. */
+@Singleton
+public final class PreflightLabServerReleaseHandler {
+
+  private final PreflightLabServerReleaseActionHelper preflightLabServerReleaseActionHelper;
+
+  @Inject
+  PreflightLabServerReleaseHandler(
+      PreflightLabServerReleaseActionHelper preflightLabServerReleaseActionHelper) {
+    this.preflightLabServerReleaseActionHelper = preflightLabServerReleaseActionHelper;
+  }
+
+  public ListenableFuture<PreflightLabServerReleaseResponse> preflightLabServerRelease(
+      PreflightLabServerReleaseRequest request, UniverseScope universe, Optional<String> username) {
+    return preflightLabServerReleaseActionHelper.preflightLabServerRelease(
+        request, universe, username);
+  }
+}
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandler.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandler.java
index fd14447efb..7be6faa208 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandler.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandler.java
@@ -26,7 +26,7 @@
 import com.google.devtools.mobileharness.api.query.proto.FilterProto;
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.DeviceInfo;
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.LabQuery;
-import com.google.devtools.mobileharness.fe.v6.service.host.builder.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.RemoteControlUrlBuilder;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDeviceConfig;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesRequest;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesResponse;
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/BUILD b/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/BUILD
index 9b7f3f4321..80928e1ea6 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/BUILD
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/BUILD
@@ -59,7 +59,8 @@ java_library(
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/device/handlers",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/device/handlers:logcat_action_helper",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/device/handlers:screenshot_action_helper",
-        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/provider",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/shared/auth",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/shared/providers:configuration_provider",
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/OssStubsModule.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/OssStubsModule.java
index 8d03f07e04..baa11101fe 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/OssStubsModule.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/shared/OssStubsModule.java
@@ -27,8 +27,12 @@
 import com.google.devtools.mobileharness.fe.v6.service.device.handlers.OssTestbedConfigBuilderImpl;
 import com.google.devtools.mobileharness.fe.v6.service.device.handlers.ScreenshotActionHelper;
 import com.google.devtools.mobileharness.fe.v6.service.device.handlers.TestbedConfigBuilder;
-import com.google.devtools.mobileharness.fe.v6.service.host.builder.NoOpRemoteControlUrlBuilder;
-import com.google.devtools.mobileharness.fe.v6.service.host.builder.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.NoOpPopularFlagsBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.NoOpRemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.PopularFlagsBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.handlers.NoOpPreflightLabServerReleaseActionHelper;
+import com.google.devtools.mobileharness.fe.v6.service.host.handlers.PreflightLabServerReleaseActionHelper;
 import com.google.devtools.mobileharness.fe.v6.service.host.provider.HostAuxiliaryInfoProvider;
 import com.google.devtools.mobileharness.fe.v6.service.host.provider.OssHostAuxiliaryInfoProviderImpl;
 import com.google.devtools.mobileharness.fe.v6.service.shared.auth.GroupMembershipProvider;
@@ -91,8 +95,12 @@ protected void configure() {
         .in(Singleton.class);
 
     bind(HostAuxiliaryInfoProvider.class).to(OssHostAuxiliaryInfoProviderImpl.class);
+    bind(PreflightLabServerReleaseActionHelper.class)
+        .to(NoOpPreflightLabServerReleaseActionHelper.class)
+        .in(Singleton.class);
+    bind(PopularFlagsBuilder.class).to(NoOpPopularFlagsBuilder.class).in(Singleton.class);
     bind(LogcatActionHelper.class).to(NoOpLogcatActionHelper.class).in(Singleton.class);
-    bind(RemoteControlUrlBuilder.class).to(NoOpRemoteControlUrlBuilder.class);
+    bind(RemoteControlUrlBuilder.class).to(NoOpRemoteControlUrlBuilder.class).in(Singleton.class);
     bind(ScreenshotActionHelper.class).to(NoOpScreenshotActionHelper.class).in(Singleton.class);
     bind(GroupMembershipProvider.class).to(NoOpGroupMembershipProvider.class).in(Singleton.class);
     bind(TestbedConfigBuilder.class).to(OssTestbedConfigBuilderImpl.class).in(Singleton.class);
diff --git a/src/java/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadiness.java b/src/java/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadiness.java
index ffaa76b310..ea7e69f72d 100644
--- a/src/java/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadiness.java
+++ b/src/java/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadiness.java
@@ -63,7 +63,7 @@ public boolean isLabServerStopReady() {
   }
 
   public boolean isLabServerReleaseReady() {
-    return false;
+    return true;
   }
 
   public boolean isLabServerDeployReady() {
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/BUILD b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/BUILD
index e9e7949cba..0bfa9e7862 100644
--- a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/BUILD
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/BUILD
@@ -29,7 +29,8 @@ java_library(
         "//src/devtools/mobileharness/fe/v6/service/proto/host:host_service_java_proto",
         "//src/devtools/mobileharness/shared/labinfo/proto:lab_info_service_java_proto",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host:host_service_logic_impl",
-        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/provider",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/shared",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/shared/providers:lab_info_provider",
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImplTest.java b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImplTest.java
index 912e7d20d1..d42c0d66fe 100644
--- a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImplTest.java
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/HostServiceLogicImplTest.java
@@ -25,10 +25,16 @@
 import static org.mockito.Mockito.when;
 
 import com.google.common.util.concurrent.ListeningExecutorService;
-import com.google.devtools.mobileharness.fe.v6.service.host.builder.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.PopularFlagsBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.handlers.PreflightLabServerReleaseActionHelper;
 import com.google.devtools.mobileharness.fe.v6.service.host.provider.HostAuxiliaryInfoProvider;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetHostHeaderInfoRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.GetPopularFlagsResponse;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.HostHeaderInfo;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
 import com.google.devtools.mobileharness.fe.v6.service.shared.SubDeviceInfoListFactory;
 import com.google.devtools.mobileharness.fe.v6.service.shared.providers.LabInfoProvider;
 import com.google.devtools.mobileharness.fe.v6.service.shared.remotecontrol.RemoteControlEligibilityChecker;
@@ -68,6 +74,8 @@ public final class HostServiceLogicImplTest {
   @Bind @Mock private InstantSource instantSource;
   @Bind @Mock private FeatureManagerFactory featureManagerFactory;
   @Bind @Mock private LabSyncStub labSyncStub;
+  @Bind @Mock private PopularFlagsBuilder popularFlagsBuilder;
+  @Bind @Mock private PreflightLabServerReleaseActionHelper preflightLabServerReleaseActionHelper;
   @Mock private FeatureManager featureManager;
 
   private HostServiceLogicImpl hostServiceLogicImpl;
@@ -109,4 +117,47 @@ public void getHostHeaderInfo_invalidUniverse_fails() throws Exception {
             ExecutionException.class, () -> hostServiceLogicImpl.getHostHeaderInfo(request).get());
     assertThat(e).hasCauseThat().isInstanceOf(IllegalArgumentException.class);
   }
+
+  @Test
+  public void preflightLabServerRelease_success() throws Exception {
+    PreflightLabServerReleaseRequest request =
+        PreflightLabServerReleaseRequest.newBuilder().setUniverse("universe").build();
+    PreflightLabServerReleaseResponse response =
+        PreflightLabServerReleaseResponse.getDefaultInstance();
+
+    when(preflightLabServerReleaseActionHelper.preflightLabServerRelease(any(), any(), any()))
+        .thenReturn(immediateFuture(response));
+
+    PreflightLabServerReleaseResponse actualResponse =
+        hostServiceLogicImpl.preflightLabServerRelease(request, Optional.of("user")).get();
+
+    assertThat(actualResponse).isEqualTo(response);
+  }
+
+  @Test
+  public void preflightLabServerRelease_invalidUniverse_fails() throws Exception {
+    PreflightLabServerReleaseRequest request =
+        PreflightLabServerReleaseRequest.newBuilder().setUniverse("invalid").build();
+
+    when(universeFactory.create("invalid")).thenThrow(new IllegalArgumentException("invalid"));
+
+    ExecutionException e =
+        assertThrows(
+            ExecutionException.class,
+            () ->
+                hostServiceLogicImpl.preflightLabServerRelease(request, Optional.of("user")).get());
+    assertThat(e).hasCauseThat().isInstanceOf(IllegalArgumentException.class);
+  }
+
+  @Test
+  public void getPopularFlags_success() throws Exception {
+    GetPopularFlagsRequest request = GetPopularFlagsRequest.getDefaultInstance();
+    GetPopularFlagsResponse response = GetPopularFlagsResponse.getDefaultInstance();
+
+    when(popularFlagsBuilder.getPopularFlags(any(), any())).thenReturn(immediateFuture(response));
+
+    GetPopularFlagsResponse actualResponse = hostServiceLogicImpl.getPopularFlags(request).get();
+
+    assertThat(actualResponse).isEqualTo(response);
+  }
 }
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
index 147d616329..df478e2cde 100644
--- a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/BUILD
@@ -37,7 +37,7 @@ java_library(
         "//src/devtools/mobileharness/fe/v6/service/proto/host:host_service_java_proto",
         "//src/devtools/mobileharness/infra/master/rpc/proto:lab_sync_service_java_proto",
         "//src/devtools/mobileharness/shared/labinfo/proto:lab_info_service_java_proto",
-        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builder",
+        "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/builders",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/handlers",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/host/provider",
         "//src/java/com/google/devtools/mobileharness/fe/v6/service/shared",
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandlerTest.java b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandlerTest.java
new file mode 100644
index 0000000000..f609189cd8
--- /dev/null
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/PreflightLabServerReleaseHandlerTest.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.mobileharness.fe.v6.service.host.handlers;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.util.concurrent.Futures.immediateFuture;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.when;
+
+import com.google.common.util.concurrent.Futures;
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseRequest;
+import com.google.devtools.mobileharness.fe.v6.service.proto.host.PreflightLabServerReleaseResponse;
+import com.google.devtools.mobileharness.fe.v6.service.util.UniverseScope;
+import com.google.inject.Guice;
+import com.google.inject.testing.fieldbinder.Bind;
+import com.google.inject.testing.fieldbinder.BoundFieldModule;
+import java.util.Optional;
+import javax.inject.Inject;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnit;
+import org.mockito.junit.MockitoRule;
+
+@RunWith(JUnit4.class)
+public final class PreflightLabServerReleaseHandlerTest {
+
+  private static final String USERNAME = "test-user";
+  private static final String HOST_NAME = "test-host";
+  private static final PreflightLabServerReleaseRequest REQUEST =
+      PreflightLabServerReleaseRequest.newBuilder().setHostName(HOST_NAME).build();
+  private static final UniverseScope UNIVERSE = new UniverseScope.SelfUniverse();
+
+  @Rule public final MockitoRule mocks = MockitoJUnit.rule();
+
+  @Bind @Mock private PreflightLabServerReleaseActionHelper actionHelper;
+
+  @Inject private PreflightLabServerReleaseHandler handler;
+
+  @Before
+  public void setUp() {
+    Guice.createInjector(BoundFieldModule.of(this)).injectMembers(this);
+  }
+
+  @Test
+  public void preflight_delegatesToActionHelper() throws Exception {
+    PreflightLabServerReleaseResponse expectedResponse =
+        PreflightLabServerReleaseResponse.newBuilder()
+            .setReady(PreflightLabServerReleaseResponse.ReleaseReady.getDefaultInstance())
+            .build();
+
+    when(actionHelper.preflightLabServerRelease(
+            eq(REQUEST), eq(UNIVERSE), eq(Optional.of(USERNAME))))
+        .thenReturn(immediateFuture(expectedResponse));
+
+    ListenableFuture<PreflightLabServerReleaseResponse> resultFuture =
+        handler.preflightLabServerRelease(REQUEST, UNIVERSE, Optional.of(USERNAME));
+
+    PreflightLabServerReleaseResponse response = Futures.getDone(resultFuture);
+    assertThat(response).isEqualTo(expectedResponse);
+  }
+}
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandlerTest.java b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandlerTest.java
index fc3320d4eb..55732fa16e 100644
--- a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandlerTest.java
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/host/handlers/RemoteControlDevicesHandlerTest.java
@@ -31,7 +31,7 @@
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.LabData;
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.LabQueryResult;
 import com.google.devtools.mobileharness.api.query.proto.LabQueryProto.LabQueryResult.LabView;
-import com.google.devtools.mobileharness.fe.v6.service.host.builder.RemoteControlUrlBuilder;
+import com.google.devtools.mobileharness.fe.v6.service.host.builders.RemoteControlUrlBuilder;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.DeviceProxyType;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDeviceConfig;
 import com.google.devtools.mobileharness.fe.v6.service.proto.host.RemoteControlDevicesRequest;
diff --git a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadinessTest.java b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadinessTest.java
index f0e86f19c0..965c71250a 100644
--- a/src/javatests/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadinessTest.java
+++ b/src/javatests/com/google/devtools/mobileharness/fe/v6/service/util/FeatureReadinessTest.java
@@ -72,4 +72,9 @@ public void isHostDecommissionReady_returnsFalse() {
   public void isLabServerStartReady_returnsTrue() {
     assertThat(featureReadiness.isLabServerStartReady()).isTrue();
   }
+
+  @Test
+  public void isLabServerReleaseReady_returnsTrue() {
+    assertThat(featureReadiness.isLabServerReleaseReady()).isTrue();
+  }
 }