Funny thing that a time server whose only function is to provide time as a service can be off by so much. My wife noticed that the SP3 was showing the wrong time. Looking into why, I noticed that the tablet had been set to synchronize with time.windows.com as the time server. When I changed it to the nist server, I got the correct one. Don't know why MS would set their own as the preferred if they can't keep it in sync. Maybe the overwhelming demands from the many SP3s out there made it go off.