Just had the same issue.
I have an Odoird-HC2 as well, my disk used to be mounted as /srv/dev-disk-by-id-ata-WDC_........-part1 and all of a sudden it decided to mount as /srv/dev-sda1
The only think I think I have changed was the acoustic mode of the hard drive from performance to quiet. It then failed after a reboot.
I have mounted the drive as dev-sda1 and changed all the sahredfolders to match, then updated all of my dockers fingers crossed it doesn't decide to change its mind back again!
Just checked and the drive is not automounting either.
Guess I'll be building a new SD card then...