Congrats on your new SC21 Pro
Sounds like your light is in Simple Mode. Battery check does not repeat, and there is no Sunset in Simple Mode.
To go from Simple Mode to Advanced Mode, do 10H.
here is the Anduril 2 online Manual https://toykeeper.net/torches/fsm/anduril2/anduril-manual.txt
and a more complete up to date flowchart, thanks to containerfan:
https://lemmy.world/pictrs/image/963aaa7a-1c2c-4c61-bdf4-e25f7f79c9ea.png
If you are set up to reflash, I recommend this version of Anduril 2 for your SC21 Pro: (it has lower lows)
https://ghart.com/blf/firmware/hex_files/sofirn_anduril2/anduril.2022-10-12.sofirn-sc21-pro.hex