Looking at first boot log, auto-import is failing:
Nov 12 13:33:38 ubuntu systemd-udevd[575]: sdb: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sdb' failed with exit code 127.
Maybe there is a race condition, as snapd starts some time later:
Nov 12 13:33:59 ubuntu systemd[1]: Started Snap Daemon.
Looking at first boot log, auto-import is failing:
Nov 12 13:33:38 ubuntu systemd-udevd[575]: sdb: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sdb' failed with exit code 127.
Maybe there is a race condition, as snapd starts some time later:
Nov 12 13:33:59 ubuntu systemd[1]: Started Snap Daemon.