> Clearly, something has failed. The archives show no messages to... Do they show up here...
rsync -nHaxi bit0.us-west.freebsd.org::FreeBSD-mailarchive/ That is supposed to be the ultimate raw history archive of all freebsd mail since forever, or at least should be such a sort of independent delivery copy. Try importing the raw mboxes in question to search for the messages in question. > how the mailer treats cross-posts. Bcc's should also be enabled to deliver and show up, Bcc as reduced form of Cc still helps with inclusion, and also helps keep 'group / all' replies going to primary.