If you manage mail servers running exim, these 2 sites provides useful summaries of the exim command:
https://linoxide.com/linux-how-to/command-line-exim/
http://bradthemad.org/tech/notes/exim_cheatsheet.php
Cmds such as:
To remove all frozen messages: # exiqgrep -z -i | xargs exim -Mrm
To remove messages older than 30 days: # exiqgrep -o 2592000 -i | xargs exim -Mrm
(86400 * 30 days = 2592000 seconds)
