I've updated and I'm still seeing 17.3.9.9 on vbox

No, none of that.

The build version is just similar to a date of birth. It doesn’t change. It’s not supposed to change. With that in mind, see again: Build Version

Unfortunately, this is one of the rare cases where old build versions don’t get fixed. But that bug Failed to start systemd-repart.service - Repartition Root Disk is purely cosmetic and can be ignored.