I never had a battery issue with FW upgrades until this update...After 6.10 it was horrible as with most of you, about 4%/ h so in total 1.5days
Finally fixed it by following a suggestion form a forum user dahero00, would suggest it for all and hopefully it will work for you:
- Full restart of the watch
- Full charge to 100%
- Completely turn off, wait 30 minutes
- Turn it on.
After this procedure, im back to about 0.5%/h. Actually a bit better than before!
Hope it helps! Cheers!