dev -> main (#5494)

Co-authored-by: Vadim Stepanov <[email protected]>

Author: joeyorlando

README.md

@@ -1,4 +1,17 @@
-# Grafana OnCall
+# 🚨 Update: Grafana OnCall OSS 🚨
+
+As of 2025-03-11, Grafana OnCall (OSS) has entered maintenance mode and will be archived on 2026-03-24.
+While you may continue to use OnCall OSS in its current state, no further updates or new features will be introduced.
+However, we will still provide fixes for critical bugs and for valid CVEs with a CVSS score of 7.0 or higher.
+
+For users seeking a fully supported and actively maintained alternative,
+**Grafana Cloud IRM** offers a modern approach to incident response and on-call management.
+
+- [Grafana OnCall OSS updates blog](https://grafana.com/blog/2025/03/11/grafana-oncall-maintenance-mode/)
+- [Grafana Cloud IRM announcement blog post](https://grafana.com/blog/2025/03/11/oncall-management-incident-response-grafana-cloud-irm/)
+- [Migration Guide](https://grafana.com/docs/oncall/latest/set-up/migration-from-other-tools/)
+
+## Grafana OnCall
 
 <img width="400px" src="docs/img/logo.png">