So I’ve just moved my HA installation over. I’ve managed to mount the the SATA drive under /media/storage following this process: https://gist.github.com/eklex/c5fac345de5be9d9bc420510617c86b5#gistcomment-3883119
I connected monitor/keyboard to my nuc and followed the instructions, finding my uuid and then using vi to create the 80-rule. Just testing it now, but appears to work. Next step is to see if I can actually mount it to Frigate.
:EDIT: OK, changed the 80-mount rules file to mount directly into
/mnt/data/supervisor/media/ and…
IT WORKS! Frigate is now recording directly to my SATA drive as evidenced by the increasing df -ah output from the terminal.