Fetch all of the archive:
scp -r freefall:/local/mail/archive/*/freebsd-snapshots .

Expand all the "validly" formed messages to a file:
zcat $(zgrep -l 'PGP SIGNED MESSAGE' *) > ../complete.txt

We only lose 2012, and we'll loose everything before 2015 later.

XXX - don't use the following, doesn't decode body properly
Explode the mbox to files:
cat 201810* freebsd-snapshots | split -p '^From ' - snap.
The stdin trick is needed so the numbering/lettering continues properly.

Correct way to split the bodies off.
python splitbody.py arch/complete.txt arch/snap.

Bulk import, -m is used to not check if they exist till the end:
for i in arch/snap.????; do sh addinfo.sh -m $i; done

Clean things up and skip checking for ones before given date
sh addinfo.sh -c 20180900

Copy them up to freefall:
scp snapshot.* freefall:public_html/FreeBSD-snap