It was my understanding that it didn't continuously sync, but only syncs once a day. Also, previously Mitel has stated that the time on the phones will not match the actual system time, due to how often the phones update themselves off of the controller. I've similarly had a customer who needed the time to be exact, since they wanted to use it for marking people late to work, and the official word from Mitel is that the phones should not be used that way, as they are not meant to be that accurate.