More 4.0 release notes edits

Author: michaelklishin

release-notes/4.0.0.md

@@ -51,6 +51,17 @@ Quorum queues now have a default [redelivery limit](https://www.rabbitmq.com/doc
 CQv1, [the original classic queue storage layer, was removed](https://github.com/rabbitmq/rabbitmq-server/pull/10656)
 except for the part that's necessary for upgrades to CQv2 (the 2nd generation).
 
+In case `rabbitmq.conf` explicitly sets `classic_queue.default_version` to `1` like so
+
+``` ini
+# this configuration value is no longer supported,
+# remove this line or set the version to 2
+classic_queue.default_version = 1
+```
+
+nodes will now fail to start. Removing the line will make the node start and perform
+the migration from CQv1 to CQv2.
+
 ### Several Disk I/O-Related Metrics were Removed
 
 Several I/O-related metrics are dropped, they should be [monitored at the infrastructure and kernel layers](https://www.rabbitmq.com/docs/monitoring#system-metrics)
@@ -99,7 +110,8 @@ what package repositories and tools can be used to provision latest patch versio
 ## Release Artifacts
 
 RabbitMQ releases are distributed via [GitHub](https://github.com/rabbitmq/rabbitmq-server/releases).
-[Debian](https://rabbitmq.com/install-debian.html) and [RPM packages](https://rabbitmq.com/install-rpm.html) are available via Cloudsmith mirrors.
+[Debian](https://rabbitmq.com/docs/install-debian/) and [RPM packages](https://rabbitmq.com/docs/install-rpm/) are available via
+repositories maintained by the RabbitMQ Core Team.
 
 [Community Docker image](https://hub.docker.com/_/rabbitmq/), [Chocolatey package](https://community.chocolatey.org/packages/rabbitmq), and the [Homebrew formula](https://www.rabbitmq.com/docs/install-homebrew)
 are other installation options. They are updated with a delay.