Contact with multiple email addresses opted out

If you have a Contact set up in Matrix with more than one email address and all of those email addresses have (individually) hit the opt out link, if they want to start getting Matrix emails again, each of the addresses associated with the Contact have to go through the opt in process. 

Matrix will not allow another Auto Email to be saved in this scenario if just one (or a couple) but not all associated email addresses have gone through the opt in process.