I This condition is triggered when the server approves your client to leave a channel, after requesting using the Channel > Leave action, or from the server kicking you from that channel (e.g. due to the auto-close parameter).
If the channel is being auto-closed from the channel master leaving, the channel master will still be in the peer list – you won't get On Peer Disconnect, just an On Channel Leave.
You will not be able to send/blast any messages to the leaving channel during the Channel Leave event. Attempting to do so will silently fail on Relay, and cause a "channel is read-only" error on Blue.