Comment 1 for bug 1859011

We need more information to know what's happening.

You say the MTA log shows only one delivery for, e.g., F2BEEE9318, to /usr/lib/mailman/mail/mailman bounces NAME-OF-HUGE-LIST yet strings on the bounce event file finds F2BEEE9318 a total of 3929 times. Can you examine the bounce-events-ppppp.pck file with Mailman's bin/dumpdb and see what the actual bounce messages are and where they all come from?