This add-on creates a log entry for emails being sent outbound by your website. Logs are retained up to a defined length of time (31 days by default), as defined in the options of the add-on. Access to the logs can be delegated via administrator permissions.
Logs shown contain the following properties:
timestamp the message was sent
username sent to
email address sent to
message subject
If the user changes their email address, the log will not reflect the user's new email address; it always logs the actual email address being sent to at that point in time.
Logs older than the defined number of days are pruned nightly at 23:30 (11:30PM) per the board's timezone.