I have an upcoming business class trip this summer, however plans have changed. My ticket is non-refundable, however if I cancel I will get the value back in credit. I also played around with changing the tickets and noticed there is an option to change plus "Make It Refundable". I have two questions...

1. If I change my flight and the flight difference is lower, am I refunded the difference as cash, or as AA credit?
   
2. If I want to be fully refunded, would it not make sense to change the flight where the Refundable add-on and the flight cost difference cancel each other out in effect?