The auto-update function of Google did not anounce it yet for me either, however I was able to manually update it in the Play store, which worked fine. I hope this one fixes the nasty sync bug.
The sync problems still persist, at least in my case... Removing/adding device etc. didn't help.
Device: fenix 5X Mobile: S7 Edge
Have you tried it with the IOS version also? Would be quite interesting to know whether this is a platform or a general problem in your case. At least since my upgrade to 4.15.1 I have not seen any sync issues yet.
Sync issues still exist. My sync had not gone more than halfway around for a month. Sleep stopped sporadically updating 5 days ago. Yoga doesn't update. This is pathetic support. I use 645M.
