Honnestly I don’t really know.
Here’s what I did:
- I had a working (SD-less) Hassio install runing from my 32GB USB-SSD
- I flashed HassOS over the USB-SSD, plugged it back --> didn’t boot at all (no IP assigned)
- I fiddled (loaded raspbian, checked the USB-boot flag is properly set)
- Retried the USB-SSD --> still didn’t boot
- I decided to take my loss and wait for someone much more skilled to solve it… flashed hassos on a 4GB SD card, and booted. it worked
- restored my snapshot, logged in by SSH, ran df -h. Surprise! it’s actually running from the USB-SSD (I forgot to unplug it)