[doc] Update PTL documentation
Adds a call out to the release session of the PTL documentation.
It is important to release new code for branches in a specific
order (from the newest branch to the older ones)
@@ -167,6 +167,11 @@ Release cycle activities
* https://releases.openstack.org/reference/using.html#using-new-release-command
+ .. note::
+ When proposing new releases, ensure that the releases for newer branches
+ are proposed and accepted in the order of the most recent branch to the
+ older.
+
Project Team Gathering
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