GITBOOK-10: Add warning for release candidate

Author: cornehoskam

16/umbraco-engage/README.md

@@ -7,7 +7,7 @@ description: >-
 # Umbraco Engage Documentation
 
 {% hint style="warning" %}
-Umbraco Engage is only available for Umbraco 13 and 16.
+Umbraco Engage for Umbraco 16 is currently available as a Release Candidate**.** This version includes limited features and is intended for development and testing purposes only. It is not recommended for use in production environments at this time. We welcome feedback and issue reports as we work toward a stable release — please submit them via [our issue tracker on GitHub](https://github.com/umbraco/Umbraco.Engage.Issues/issues).
 {% endhint %}
 
 Umbraco Engage is a marketing suite that helps marketers and developers create personalized, data-driven experiences for website visitors. This documentation provides a complete guide for setting up analytics, A/B testing, and targeted campaigns using all the features of Umbraco Engage.

16/umbraco-engage/release-notes.md

@@ -14,4 +14,10 @@ If you are upgrading to a new major version, check the breaking changes in the [
 
 ## Release History
 
-Below are the release notes for Umbraco Engage, detailing all changes in this version.
+Below are the release notes for Umbraco Engage 16, detailing all changes in this version.
+
+#### [16.0.0-rc1](https://www.nuget.org/packages/Umbraco.Engage/16.0.0-rc1) (July 29nd 2025)
+
+This Analytics-only version has been fully rebuilt to run on the new Web Component-based Umbraco backoffice. With all dependencies upgraded to the latest versions, this upgrade has led to a more future-proof product than ever before. The Personalization, A/B Testing, and Reporting features are not yet available in this initial release candidate but will follow after a bit more polishing.
+
+To find out more about the specific upgrade notes and breaking changes, visit the [version-specific-upgrade-notes.md](upgrading/version-specific-upgrade-notes.md "mention") article.