Github user pnowojski commented on the issue:
https://github.com/apache/flink/pull/5200
Regarding the race condition. I think we meant the same thing or maybe I
misunderstood part of the code, but yes, this NPE seems like a possible outcome
of this race condition.
If you have spare cycles to fix this race feel free to do so, I would like
to avoid working on it in this and the following week because of some code
handing over before some lengthy vacation in my team.---
