[Mailman-Users] messages discarded after approval

[Matt Morgan]

One of my moderators said he had messages from a particular poster
disappear after approval, and never appear on the list.

Here are some lines from the vette log that seem to show exactly what he
reports (I've anonymized the sender address, but it matches the poster he
mentioned). What's going on here? It looks like the messages came in, were
approved a few days later, then discarded one second after approval. Am I
reading it right? If so, what would have caused this?

Jan 31 15:16:11 2017 (11509) consdistlist post from xxxx at yyyy.edu held,
message-id=<
MWHPR04MB0703EB5C6192DE93482E4AAEFF4A0 at MWHPR04MB0703.namprd04.prod.outlook.com>:
Post to moderated list
Feb 02 16:29:37 2017 (11855) consdistlist: held message approved,
message-id: <
MWHPR04MB0703EB5C6192DE93482E4AAEFF4A0 at MWHPR04MB0703.namprd04.prod.outlook.com
>
Feb 02 16:29:38 2017 (11509) Message discarded, msgid: <
MWHPR04MB0703EB5C6192DE93482E4AAEFF4A0 at MWHPR04MB0703.namprd04.prod.outlook.com
>'

Feb 03 09:29:18 2017 (11509) consdistlist post from xxxx at yyyy.edu held,
message-id=<
MWHPR04MB0703B22758AFE62336E49BEAFF4F0 at MWHPR04MB0703.namprd04.prod.outlook.com>:
Post to moderated list
Feb 06 17:35:58 2017 (6095) consdistlist: held message approved,
message-id: <
MWHPR04MB0703B22758AFE62336E49BEAFF4F0 at MWHPR04MB0703.namprd04.prod.outlook.com
>
Feb 06 17:35:59 2017 (11509) Message discarded, msgid: <
MWHPR04MB0703B22758AFE62336E49BEAFF4F0 at MWHPR04MB0703.namprd04.prod.outlook.com
>'

I checked and that address is not among the "automatically discard"
addresses in Sender Filters, in case that matters.

Thanks,
Matt