Guys, it is some topics complain fast batt drain since fw update 12.20 for f6.
To avoid repetitive copy-past please read my post https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-6-series/244808/battery-drain-on-fenix-6x-saphire-with-firmware-12-20/1163713#1163713
Please note, this negative effect can happen time to time, so to catch it up you should be patient.
Looking forward to hear your thoughts, could you do you own experiments and share outcome.