Cannot edit more than one Additional Location

I am able to create multiple Additional Locations by importing the data to a contact. But the edit interface does not allow for editing more than one additional location, or to choose which additional location to edit.

In the contact view screen, it displays everything fine, so this is really an issue of being able to attach info to a contact without being able to edit it.

The project is a college internship program, so it makes sense to store (and edit!) a permanent address, campus address, and internship / summer address for those contacts.