S20+ Black and white auto colour fade

I found that black white to colour wasn’t working reliably. I would be going from menu to Instagram, it would turn colour on for a moment then revert back to black and white.

I later found in the settings I could disable the greyscale option all together.

Has this be picked up as a bug. Also when bringing the curtain down a few times it was possible to see colour momentarily.

. I actually think I solved it myself by editing the tile to enable colour

actually when I have the color turned off and open twitter its grey. When I leave the app before the app closes it turns colored. I don’t know is this is normal or a glitch

it solved the problem for me battery drain is hugely reduced now.