Github user StephanEwen commented on the issue: https://github.com/apache/flink/pull/5427 I think we are talking about two different things here: 1. We DO need a new method on the hook interface to reinitialize the reader group. I think the one suggested by Eron works. 2. We DO NOT need a new method on the CheckpointCoordinator, but calling `Hook.initializeState()` within `CC.restoreLatestCheckpointedState()` (whenever there is no checkpoint to be restored) should work. ==> Let's add the Hook method, but not add an additional method to the CheckpointCoordinator.