I have 2 sites that are running 2014 R2HP1 that have started seeing messages mysteriously moved to trash without an automated cleanup policy in place. Some items don't make it to the inbox - just end up in trash. This does not happen to all users. These are users that do not have any specific rules in place - in fact, pretty much plain vanilla users. log files are inconclusive - GWCheck reports no issues that might shed some light on it. Problem was never encountered on 2012 or 2014 - just since 2014 R2 HP1 was applied. One system uses mobility server, the other doesn't.
Has anyone else seen this?