I installed Fedora Silverblue then Bluefin on LUKS partition, I wanted to test a rollback, so I did. All images became Bluefin, Silverblue disappeared. Does it mean, rollback, will not work on encrypted drives? Have you tried doing rollback on the LUKS drive?
I did many rollbacks on a LUKS drive, it does work. What happened in your case probably is you or the system generated another image and the Silverblue one got undeployed, since it was not pinned and only 1 or 2 images previous images are kept.
Have you also tried choosing previous images from GRUB boot menu?
Boot menu appears before LUKS is decrypted.
Yes. I’ve used Fedora Atomic (Silverblue → uBlue → My own image) for 3 years as my main OS, always encrypted and I don’t remember ever having an issue when it came to using previous images.
There is no problem on rebooting older deployments with LUKS partition.
You just have to understand that it only keeps few older deployments (cant remember is only 1 or two) and gets rid of the rest. Unless you pin the deployments. You can of course pin every deployment if you want as long as you have the hard drive space available, but you should not need to.