More than one email for Author

I’ve got a blog that allows Authors to email in the content via the Postie plugin. I have a couple of authors that have more than one email account that they need to use in various situations. (Home, work etc) How can I give a single user name, more than one email address, so that if they submit content from either email address, they get submitted as the one person. I can allow multiple email accounts in postie, but in the WordPress Authors & Users panel, each user can only have one email account.

So currently I add the person a second time with a different user name. The problem is that when they post under different email accounts, they end up with two ‘Author Profiles’ (even though they are the same person)

Any help would be greatly appreciated.