Believe it or not, but we have an abusive subscriber on our Mailchimp mailing list who's sending replies to our campaign emails with abusive and unwanted emails back to us.
I've tried to look around in Mailchimp settings but I can't see any way to do this.
It would be good to document it here if there is a solution, so others Googling in the future can find a quick answer, right here.
Can you block or blacklist an email address so that it won't be allowed to RE-subscribe to the mailing list later, if they wanted to?