Hi after update firmware my Fenix 6x Sappphire on 11.10 I have problem with battery drain fast too. But bigger problems it is, that wifi is broken (no searching wifi - nothing)
In system info is only information about wifi version 655.35. If I manaualy upload wifii driver GUP2196.GCD into "GARMIN\RemoteSW, update is triggered after unplug from PC, update is install but after reset:
still version wifi 655.35
wifi does nost work
and GUP2196.GCD is not deleted from folder "GARMIN\RemoteSW a it can be triggered again, again. Still exists in MENU update
Downgrade system on 10.10 is possible, but zero effect on problem with wifi.
It looks like same problem in https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-5-plus-series/154347/fenix-5-plus---wifi-broken---wifi-software-reporting-655-35 .