It's been useful to me several times and the format doesn't change. Maybe it's useful to you too. But it's getting no work, its archived, just take what you want.
A so hacky that it should've been a bash script golang program for parsing exim4 logs to pull a csv of emails against their "owners".
Reads exim4 email server logs to create a list of email addresses sent to (regex match -ignore "^$" so you can discard internal mail/spam) grouped by email sent from (regex match -email ".*" so you can ignore no-reply etc). Results in a file with email addresses sent to by local addresses. Outbound emails only. I've had it churn through a five or so years worth of email logs without too much trouble.