relatedly, I used to use a 4x bay USB3 caddy for some disks.. It was OK, but didn't expose the raw disks and the controller was pretty fucky swallowing things like SMART.
Are you running something like Unraid or TrueNAS, or are you just running a 'regular' Linux distro?
Ubuntu + ZFS. I don't see the appeal of running a non-mainline distribution. All I did was set it up so ZFS sends me emails and a crontab to run a ZFS resilver weekly.
My main beef with that MediaTek X2x platform is the hella dated hacked up kernel it was stuck with which meant the damn thing never got mainlined so my Planet Gemini has been nothing but a paperweight.
Did a system upgrade overwrite your grub config?