I’m a happy user of OSMC and will migrate towards bullseye when it will became officially available here.
But since I use a lot of other tools on the same raspberry using special repositories I can’t simply upgrade. Instead I plan to setup from scratch based on a fresh OSMC image. Next will be to get ssh access to tweak all my OS specific settings (including e. g. GPIO settings and the like).
Is it OK to get all OSMC/kodi settings back simply by restoring the original /home/osmc/. kodi folder? Of course it’s the same hardware (pi3) and the same OSMC (Kodi 19.4), but a different base OS (buster vs. bullseye).