Following a shutdown -r -t 1, the drive appears briefly in Windows explorer, but disappears before any checks can be made. I guess the firmware tells it to disconnect. It has two (NTFS) partitions, each several TB. A Seagate Backup Plus Hub, not that old.
The first question is, should I try to open the box and connect as SATA? Back in the old days, that would have its pros and cons, but I could always take a different SATA-to-USB2 interface and no damage was done; but I have not had a disk crash since the era of USB2, so better ask.
I have a backup only a few weeks old, so I am not panicking – but once I get it connected I would very much want to get it to read in order of last modified. Like first getting out the NTFS metadata to see what was altered when, and then I guess I will have to think over whether I should discard it and do the work over, doing it the second time isn't as time-consuming as the first.