I believe it has been fixed.
Just tested it and it seems to be changing to Dark mode in conjunction with Night Shift again.
Upon further testing, it's only partially been fixed for me.
Before:
Night Shift is set to custom.
Night Shift changes as scheduled.
Dark Mode switches on at the same time as Night Shift.
After 14.4:
Night Shift is set to custom.
Night Shift changes as scheduled.
Dark Mode doesn't switch on at the same time as Night Shift. It turns on at some other (random) time.
Under Appearance, If I click "Auto" during Night Shift hours, it still stays on Light mode.
Manually turning on Dark mode is the only option.
After 14.4.1:
Night Shift is set to custom.
Night Shift changes as scheduled.
Dark Mode doesn't switch on at the same time as Night Shift. It turns on at some other (random) time.
Under Appearance, If I click "Auto" during Night Shift hours, it correctly recognizes that Dark Mode should be on.
Manually clicking "Light Mode" then "Auto" seems to correctly calibrate it, but I still have to manually do this.
So we're one step closer to fixing this, as at least the "Auto" seems to understand that Dark mode should be on.
It just doesn't do it by itself until I toggle it on/off.