When statistics for a group assignment are updated, there may be some very specific state of a submission/group/personal overriden grade/? which causes an issue where Hibernate tries to lazy load a collection from a detached object during statistics update.
Fix: In case of a failed attempt, reload all submissions into the session in the seconds attempt when updating the statistics.

Submitted by Elmer van Chastelet on 4 November 2022 at 08:28