We have noticed that the Automated Behavior field for Last Sent still gets populated with the date the an email is sent even if the person is on the master suppression list and not actually sent the email.

The individual DID exist in the original contact source but is on the master suppression list so should never have received the email. Ideally, this field would be left blank, as it is confusing to see that a recipient has a date for "Last Sent" but no Contact Insight history.

I understand there is a difference between "sending a mailing" (as a whole) and sending a mailing (per recipient). It's almost like the label should be "Attempted Last Sent" instead of "Last Sent" because the semantics are a little confusing.