What do you mean by constantly appearing? Do you mean endlessly repeating or that they just repeat a number of times equal to the number of expected recipients of the post?
Sorry, I meant endlessly repeating.
This is a piece from debug after sending an email to the list from a recipient that does not need moderation:
Dec 27 11:41:10 2019 (11473) [outgoing] <function deliver at 0x7f7c3de987b8>: <CAOwJ5NX+K3CORg9riHc2T1dbdKZLZojHT1MVs44Wd3SbTJju6A@mail.gmail.com> Dec 27 11:41:10 2019 (11473) Using agent: <mailman.mta.bulk.BulkDelivery object at 0x7f7c3de264a8> Dec 27 11:41:10 2019 (11468) [BounceRunner] starting oneloop Dec 27 11:41:10 2019 (11468) [BounceRunner] ending oneloop: 0 Dec 27 11:41:10 2019 (11473) Cannot connect to SMTP server 127.0.0.1 on port 25 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] finishing filebase: 1577457670.0510046+6fe6039c1b0b65672aade3bfced1aca2fe8afa16 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] doing periodic Dec 27 11:41:10 2019 (11473) [OutgoingRunner] committing transaction Dec 27 11:41:10 2019 (11473) [OutgoingRunner] checking short circuit Dec 27 11:41:10 2019 (11473) [OutgoingRunner] ending oneloop: 1 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] starting oneloop Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing filebase: 1577457670.5784276+6f5454f4a57da4dc15912e789f0719be53c74616 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing onefile Dec 27 11:41:10 2019 (11473) [outgoing] <function deliver at 0x7f7c3de987b8>: <CAOwJ5NX+K3CORg9riHc2T1dbdKZLZojHT1MVs44Wd3SbTJju6A@mail.gmail.com> Dec 27 11:41:10 2019 (11473) Using agent: <mailman.mta.bulk.BulkDelivery object at 0x7f7c3de26e10> Dec 27 11:41:10 2019 (11470) [IncomingRunner] starting oneloop Dec 27 11:41:10 2019 (11470) [IncomingRunner] ending oneloop: 0 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] finishing filebase: 1577457670.5784276+6f5454f4a57da4dc15912e789f0719be53c74616 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] doing periodic Dec 27 11:41:10 2019 (11473) [OutgoingRunner] committing transaction Dec 27 11:41:10 2019 (11473) [OutgoingRunner] checking short circuit Dec 27 11:41:10 2019 (11473) [OutgoingRunner] ending oneloop: 1 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] starting oneloop Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing filebase: 1577457670.61572+a2844469514ead14dedcee020ad8e2a34036f8ef Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing onefile Dec 27 11:41:10 2019 (11473) [outgoing] <function deliver at 0x7f7c3de987b8>: <CAOwJ5NX+K3CORg9riHc2T1dbdKZLZojHT1MVs44Wd3SbTJju6A@mail.gmail.com> Dec 27 11:41:10 2019 (11473) Using agent: <mailman.mta.bulk.BulkDelivery object at 0x7f7c3de26f28> Dec 27 11:41:10 2019 (11473) [OutgoingRunner] finishing filebase: 1577457670.61572+a2844469514ead14dedcee020ad8e2a34036f8ef Dec 27 11:41:10 2019 (11473) [OutgoingRunner] doing periodic Dec 27 11:41:10 2019 (11473) [OutgoingRunner] committing transaction Dec 27 11:41:10 2019 (11473) [OutgoingRunner] checking short circuit Dec 27 11:41:10 2019 (11473) [OutgoingRunner] ending oneloop: 1 Dec 27 11:41:10 2019 (11473) [OutgoingRunner] starting oneloop Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing filebase: 1577457670.6512213+13fe7854257bb1a494f797f480cb10733bd440ac Dec 27 11:41:10 2019 (11473) [OutgoingRunner] processing onefile Dec 27 11:41:10 2019 (11473) [outgoing] <function deliver at 0x7f7c3de987b8>: <CAOwJ5NX+K3CORg9riHc2T1dbdKZLZojHT1MVs44Wd3SbTJju6A@mail.gmail.com> Dec 27 11:41:10 2019 (11473) Using agent: <mailman.mta.bulk.BulkDelivery object at 0x7f7c3dd44390> Dec 27 11:41:10 2019 (11469) [CommandRunner] starting oneloop Dec 27 11:41:10 2019 (11469) [CommandRunner] ending oneloop: 0
This is endlessly repeating with different filebase