Is your 735 connected to the mobile app?
Have you got any Strava segments in Training, Strava Live Segments?
I noticed mine seem to be doing lots of synching.
No Strava Live Segments, but it is connected to the mobile app a fair amount, no more than usual, 'though.Didn't connect to the mobile app since last night and it is still draining the batter incredibly fast. More than 50% drained in about 15 hours with no GPS and half of this was sleeping.