postfix/smtpd[5364]: connect from source.com[X.X.X.X]
…
postfix/smtpd[5364]: NOQUEUE: client=source.com[X.X.X.X]
postfix/smtpd[5372]: connect from amavis[internal24]
postfix/smtpd[5372]: D6749620E2: client=amavis[internal24], orig_client=source.com[X.X.X.X]
postfix/cleanup[5373]: D6749620E2: message-id=<o73vp3cKZBsxE85eDO@rbh.source.com>
postfix/qmgr[12066]: D6749620E2: from=<sender@source.com>, size=5076, nrcpt=1 (queue active)
postfix/smtpd[5372]: disconnect from amavis[internal24]
postfix/smtpd[5364]: proxy-accept: END-OF-MESSAGE: 250 2.0.0 from MTA(smtp:[internal25]:10025): 250 2.0.0 Ok: queued as D6749620E2; from=<sender@source.com> to=<recipient@postfix> proto=ESMTP helo=<source.com>
postfix/smtpd[5364]: disconnect from source.com[X.X.X.X]
postfix/smtp[5374]: D6749620E2: to=<forwarded@me.com>, orig_to=<recipient@postfix>, relay=mx4.mail.icloud.com[17.178.97.73]:25, delay=3.1, delays=0.07/0.01/1.7/1.3, dsn=5.7.1, status=bounced (host mx4.mail.icloud.com[17.178.97.73] said: 550 5.7.1 [CS01] Message rejected due to local policy. Please visit https://support.apple.com/en-us/HT204137 (in reply to end of DATA command))
postfix/cleanup[5373]: 198966214E: message-id=<20181003055857.198966214E@host.postfix>
postfix/qmgr[12066]: 198966214E: from=<>, size=7279, nrcpt=1 (queue active)
postfix/bounce[5375]: D6749620E2: sender non-delivery notification: 198966214E
postfix/cleanup[5373]: 2E1286214F: message-id=<20181003055857.2E1286214F@host.postfix>
postfix/qmgr[12066]: 2E1286214F: from=<double-bounce@host.postfix>, size=4880, nrcpt=1 (queue active)
postfix/bounce[5375]: D6749620E2: postmaster non-delivery notification: 2E1286214F
postfix/qmgr[12066]: D6749620E2: removed
postfix/smtp[5374]: 198966214E: to=<sender@source.com>, relay=source.com[185.207.8.246]:25, delay=0.14, delays=0.08/0/0.05/0, dsn=4.0.0, status=deferred (host source.com[185.207.8.246] refused to talk to me: 421 Too many concurrent SMTP connections; please try again later.)