I unfortunately forgot to include on the above - in my first post I had
topped up the charge at 7am from 80% to 95% so total drain from 7am to 2pm (7
hrs) was 35% as the battery was down to 60% at 2pm. At this point I turned off
active noise detection to see if that made any change. When I took my watch off
to charge at 9pm it was down to 35% which is still about twice as much battery
drain throughout the day compared to what my Series 4 had previously.
Last night (while charging) I updated to WatchOS 6.0.1, turned off raise
to wake (so my overnight usage should have been at a consistent 1hz refresh
rate at minimum brightness), turned off walkie-talkie and did a restart of my
phone and watch. After 7 hrs of sleep the watch battery was down to 85% (having
had lost 15%) during a theoretical minimal use window (i.e. no calls,
notifications, accelerometer, etc). This was still twice the comparative
overnight drain experienced from my Series 4 which was not promising.
I charged the watch back up to 100% at 7am before leaving for work and
am now at 84% at 10:30am which equates to 4.5% drain per hour of low demand
usage (driving, typing, standing). Best case scenario based on that rate of
usage will be having 35% battery remaining at 10pm when I get to charge it
again which doesn't take into account the 2 x 30 minute workouts I have planned
for today. Expected charge remaining taking into account the workouts looks to
be around 25% again which is what I had been tracking (see 2nd paragraph in
previous post above) prior to updating to 6.0.1, turning off noise detection,
turning off walkie-talkie, etc. As mentioned, this is about 40% worse battery
life for the same usage than I was seeing on my series 4 with WatchOS 5 so as a
result I'll be turning these features back on as they are not the cause it
appears. As mentioned previously, the same Series 4 watch is also seeing
noticeably worse battery life after updating to WatchOS 6 also.
On a related note, some WatchOS 6.1 beta testers have advised that the
6.1 software update appears to address their battery draining issues which is a
promising sign but proceed at your own risk given no news on the public release
date of 6.1.