The SD card (mmcblk0p2) is refreshed as a live boot-fallback clone of
NVMe root after pushes, but that rsync was being hand-typed each time
and its exclude list didn't cover /etc/fstab. That let it clobber the
SD's own fstab with the NVMe's PARTUUIDs, breaking SD-only boot (only
mounts correctly if the NVMe happens to also be present). Also excludes
/etc/machine-id and /var/log so the clone doesn't inherit the NVMe's
identity/journal history.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>