Battery drain

A temporary increase in power consumption after a macOS update is not unusual. "Temporary" might mean a few hours, even the better part of a day.

View Battery Usage History on a Mac notebook - Apple Support provides a broad overview of battery usage.

View energy consumption in Activity Monitor on Mac - Apple Support provides app-specific usage.

For more information read About battery health management in Mac notebooks - Apple Support.

You may have what I'm seeing: while sleeping overnight my Macbook Air M1 13" keeps waking up every ~15 min, some people think due to bluetooth being on and maybe also having accessories like Magic Keyboard, Mouse or Trackpad paired. This will drain the battery significantly - possibly to 0%.

Or if you have it plugged in to AC it won't drain but it won't stay asleep either - which I don't like because it keeps the battery at 100% vs before the smart battery management kept my battery at 80% (since I keep it plugged in a lot).

12.2.1 supposedly addressed a similar-sounding issue for Intel-based macs -- hope an M1-based fix is on the way.

In Terminal run "pmset -g log | grep -i "wake from" and if you see lots of entries like this you may have the same issue... in which case people either say turn off Bluetooth or shut down vs sleep...

2022-02-10 17:33:09 -0800 DarkWake DarkWake from Deep Idle [CDNPB] : due to NUB.SPMI0Sw3IRQ nub-spmi.0x02 rtc/SleepService Using AC (Charge:100%) 45 secs