Did a little digging into the code, I suspect this is a bug in the current `AgentScheduler` code - `SessionKeys` should use SessionId as the hashtag to ensure related session data goes to the same slot (https://redis.io/blog/redis-clustering-best-practices-with-keys/ for more info).
EDIT: It initially looked like this fixed the error. Closer inspection of the logs shows that it’s still failing, will continue to look for workarounds.