HassOS has rolled itself back to 1.12 from 1.13, and when I tried to upgrade back to 1.13 it won't boot

I’ve been using HassOS since 1.12 and it worked well, and upgraded to 1.13 when it was released a few months back and it’s been great ever since.

However today I found the it had gone back to 1.12 after a reboot, so I then tried to upgrade it to 1.13. Since clicking ‘upgrade’ I can no longer access HassOS, no webinterface, no SSH access, yet it’s still on my LAN, as it responds to PING’s on it’s IP address.

How can I fix this? I’m running HassOS on a RPi3, high quality SD card, official PSU, and database mounted on a network share.

Ok, after powering off the Pi for a while and back on it seems to have gone back to 1.13.

Are there any commands I can run to check the health of the SD card?