==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.3.2
- Deployed with iRedMail Easy or the downloadable installer? Downloadable Installer
- Linux/BSD distribution name and version:  Debian GNU/Linux 10 (buster) [x86_64]
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL/MariaDB
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

In daily logwatch mails there are a huge amount of unmatched entries with the standard configuration of iRedMail, which was deployed in July/2020 as version 1.3.1 and now updated to version 1.3.2:

1   Nov  5 06:49:42 www postfix/qmgr[7866]: 4CRXfG5616zM7DCl: from=... size=35158, nrcpt=1 (queue active)
1   Nov  5 04:02:25 www postfix/pipe[4974]: 4CRSxD18g8zM7HSf: to=...  dsn=2.0.0, status=sent (delivered via dovecot service)
1   Nov  5 12:22:26 www postfix/qmgr[7866]: 4CRh2B56SpzM7DCl: from=..., size=9579, nrcpt=1 (queue active)
1   Nov  5 09:24:37 www postfix/cleanup[28025]: 4CRc511HkfzM7KPC: message-id=...zf6a@emailsocket.com>
1   Nov  5 08:04:37 www postfix/qmgr[7866]: 4CRZJj0xhRzM7KP0: removed
... 
and many more

These are all very common log entries which should match in any case. In the former Debian version 8 (Jessie) all such entries matched.

Nov  8 03:30:04 www postfix/qmgr[11525]: F34C180582: removed

The only difference seems to be that the id of the mail was a hexadecimal number (10 digits) and now it's a string with 16 characters.