Case 1: Tuleap provides easy access to the end-user to the Tuleap official release note
When your Tuleap server is updated, the URL to the Tuleap official release notes is automatically up to date. Your users are informed with a star in the Help dropdown at the bottom right. You have nothing to do.
Case 2: You want to update the release notes URL provided
Go to the platform administration and click on “Release note link”. You will be able to edit the release note link.
Case 3: You do not want to use the official Tuleap release notes
You will need your own web page to present the release notes. And follow Case 2 each time you upgrade.