Gaps in sync

The following happened on iOS. Something similar is happening on Android but not at the same times.

I was away for a few days, and when syncing my Tags with the RuuviStation, the sync for almost all of my 10 Tags had a gaps. I was away on Sep 2-5 (returned on Sep 5 at 22:30). The sync results

  • data from Sep 2 until Sep 5 12:00
  • no data on Sep 5 12:00 until Sep 6 2:00
  • I synced late on Sep 5 (or maybe on Sep 6 at 2:00)
  • data on Sep 6 2:10-2:20
  • no data on Sep 2:20-15:10
  • data on Sep 6 at 15:10
  • no data on Sep 6 15:10-21:30
  • ok data since then

I am really puzzled my there were gaps, why the gaps were similar for all Tags, why the gaps did not align with my absence. Just puzzles. I am confused. I installed my Gateway on Sep 6 in the evening, so even that should not have interfered with the syncs on Sep 5.

Also, I did some syncs later too, on Sep 6 during the day or at least in the evening.