Update v1.2.adoc

Author: jerouris

guides/release-notes/v1.2.adoc

@@ -3,7 +3,7 @@
 Release date::	November 2025
 				* Date of member review:	2025-10-27
 				* Date of publication:		2025-12-08
-				* Mandatory to use from:	2026-02-23
+				* Mandatory to use from:	2026-03-16
 
 [NOTE]
 ====