We updated to S216 on both hoppers overnight and the problem with timers showing as canceled by user is still occurring.
It is very easy to duplicate. Set up 3 half hour programs to record at the same time. Then create 3 new timers (all on different channels) for the next half hour. Turn off the hopper and make sure no joey is watching anything. The first 3 recordings work fine. Two of the next timers also work fine. The last timer will not record and has the message "Cancelled: By user Office".
I've tested this on both hoppers. I think that if I had been watching one of the programs on the hopper live during the test it would have asked about changing channels but nobody was watching. Normally this happens in the evening when we are watching recorded programs and it does NOT ask about changing channels when you are watching something previously recorded.