Backlight settings and sleep time not working

I just bought a Descent Mk2 and mostly love it except one annoying quirk. The backlight settings do not change during sleep time. It does not seem to matter what combination of settings I choose.

At the moment my watch is set up so that during sleep time the backlight should behave as follows:

keys: off

alerts: off

gesture: off

timeout: 4 secs

brightness: 10%

During normal wear i.e. settings under 'not during activity' the backlight should behave as follows:

keys: on

alerts: on

gesture: on

timeout: 8 secs

brightness: 50%

All these settings will change when I change them and behave as I expect it would.

Essentially the goals is to just have it that if I really want to see the time when sleeping I can press the light button and see it without blinding myself. I have set up DND mode to come on automatically during sleep time and this disables the gesture and alerts setting and is something of a workaround (at least I'm not blinding myself when I roll over half asleep).

Wondering if anyone else is having similar issues. Hoping not to do a factory reset with all the time spent adjusting the settings - most of which work as expected except this one.