More 3.13.0 release notes polishing

release-notes/3.13.0.md

@@ -43,14 +43,20 @@ what package repositories and tools can be used to provision latest patch versio
 See the [Upgrading guide](https://www.rabbitmq.com/upgrade.html) for documentation on upgrades and [RabbitMQ change log](https://www.rabbitmq.com/changelog.html)
 for release notes of other releases.
 
+Note that since 3.12.0 requires **all feature flags** to be enabled before upgrading,
+there is no upgrade path from from 3.11.24 (or a later patch release) straight to 3.13.0.
+
 ### Required Feature Flags
 
-TBD
+This release does not [graduate](https://rabbitmq.com/feature-flags.html#graduation) any feature flags.
+
+However, all users are highly encouraged to enable all feature flags before upgrading to this release from
+3.12.x.
 
 ### Mixed version cluster compatibility
 
-RabbitMQ 3.13.0 nodes can run alongside `3.12.x` nodes. `3.12.x`-specific features can only be made available when all nodes in the cluster
-upgrade to 3.13.0 or any other patch release in the new series.
+RabbitMQ 3.13.0 nodes can run alongside `3.12.x` nodes. `3.13.x`-specific features can only be made available when all nodes in the cluster
+upgrade to 3.13.0 or a later patch release in the new series.
 
 While operating in mixed version mode, some aspects of the system may not behave as expected. The list of known behavior changes is covered below.
 Once all nodes are upgraded to 3.13.0, these irregularities will go away.
@@ -73,6 +79,8 @@ on older Erlang releases.
 ### Client Library Compatibility
 
 Client libraries that were compatible with RabbitMQ `3.12.x` will be compatible with `3.13.0`.
+RabbitMQ Stream Protocol clients must be upgraded to use the stream filtering feature
+introduced in this release.
 
 
 ### Getting Help