Anyone know what happens to the settings once the battery gets down to 20% ish ? I’ve got it on test now, but I seem to think it just autoswitches to a mid setting, then low (?) just to extend life ?

yep sounds about right, what are you trying to find out ultimately?

You can switch it back up to high if you want though.

My MKII just switches onto flashing mode to get you home having gone through to low setting first. I believe it doesnt do the battery any good to conmpletely flatten it to no light at all.
Normally get about 3 to 3 and a hlf hours from mine temperature dependant.

mine goes for over 3 hrs on full, never had it power down

yep sounds about right, what are you trying to find out ultimately?

24h solo coming up so I’m wondering if I can struggle through with singlecell piggy back on high / medium mix (9 hour light required) or if I should take 150g extra and just hire a triple cell ?