That's very interesting and I really appreciate your interest and support, you've done more than anybody has since I got myself into this situation on the 20th

That's very interesting and I really appreciate your interest and support, you've done more than anybody has since I got myself into this situation on the 20th of November. I have two SSDs each with an individual (encrypted) APFS volume. One (labelled Radix) is the boot volume and ends up mounted on /. The other one (labelled Usor) is meant to mount on /Users, but on account of being encrypted, gets ignored by automount (despite having a valid /etc/fstab entry) and just lingers, until I log in into a utility account, allow it to decrypt and mount, log out, and log back in as my user. My user has the home folder set to /Volumes/Usor/User/james and then it all works. But as lament, half the stuff is broken. As soon as I get back to the office I'll have a look at whether the ignore-permissions flag is set or not (I reckon it isn't, but it is worth checking). I've faced more path-blocking absurdities in this enterprise than I have in the past ten-plus years of Mac usership.