Long training day gets reset on sync to Garmin Connect

I have a Forerunner 165 where I want my long training day to be on saturday and on my Edge 840 to have my long training day on sunday. But when I sync the devices with Garmin Connect these days often end up on the same day. Sometimes Forerunner moves to sunday and sometimes Edge 840 moves to saturday, so my long training day always end up on the same day. Anyone else that has this problem?