Update release notes and home page notification

Author: asavageiv

docs/EN/Maintenance/ReleaseNotes.md

@@ -54,6 +54,23 @@ WearOS 5, API level 34 (Android 14) has [limitations](#BuildingAapsWearOs-WearOS
 
 (latestrelease)=
 
+(version3421)=
+
+## Version 3.4.2.1
+
+- Equil: fix Pairing and progress dialog @MilosKozak
+
+(version3420)=
+
+## Version 3.4.2.0
+
+Release date: 04-02-2026
+
+- Equil: Fix resistance for different models @hhfcvmars
+- Tidepool: Fix session @MilosKozak
+- Medtrum: Fix activation path by preveting double fill @MilosKozak
+- COB: Fix COB calculation (covers dangerous edge case) @MilosKozak
+
 (version3410)=
 
 ## Version 3.4.1.0

docs/EN/index.md

@@ -5,7 +5,7 @@
 ```{admonition} Latest Release
 :class: note
 
-8 March 2026 : Version 3.4.1 is out. Check the [Release Notes](#latestrelease) to see what's new.
+ 31 March 2026 : Version 3.4.2.1 is out. Check the [Release Notes](#latestrelease) to see what's new and follow the instructions in the [update manual](UpdateToNewVersion) to update to a the version.
 
 ```