Colour/Contrast issues in photoshop beta

I see there is a new 27.12 beta release, but cant see any release notes relating to the ongoing colour issues in previous releases (after 27.9) being resolved? can anyone confirm?  also, usually there are only 3 previous versions available to roll back to, with 27.12 does this mean 27.9 (last working version) also will dissapear?  Normallly i would test this out but dont want to lose access to the last working version 27.9

Cheers