[SOLVED] What does bpo11 mean?

This means that it was backported (bpo) from a newer version to Bullseye (11).
 
PVE 8 is already on 6.2.16, and this package is basically a backport to PVE 7 (Bullseye).
So the naming changed.
ZFS was kept at 2.1.11 since it's not planned to introduce a newer version in PVE 7 (for now). It should stay compatible with kernel 5.15 in this regard.
 
PVE 8 is already on 6.2.16, and this package is basically a backport to PVE 7 (Bullseye).
So the naming changed.
ZFS was kept at 2.1.11 since it's not planned to introduce a newer version in PVE 7 (for now). It should stay compatible with kernel 5.15 in this regard.

Got it! Appreciate the info!