A refundable American Airlines ticket with a $150 cancellation fee would be unusual. I'm not saying that Disney couldn't have worked out an unusual contract with American Airlines, just that I've never heard of such a thing.
Normally, tickets are either fully refundable (in which case they're usually quite expensive) or nonrefundable (but the value of a ticket cancelled at the passenger's request is applicable toward another nonrefundable ticket ON THE SAME AIRLINE, minus a $150 change fee).
However, American Airlines should get you to your destination, and there should be no change fee if AA puts you on different flights to fulfill their obligation to you. It could mean flights on a different airline.
Even on its worst days last week, American only cancelled 4% to 6% of its flights. American moved passenger to other flights and other airlines if necessary.
In the case of a pilot's strike (which American says would be illegal while the airline is in Chapter 11), American will offer full refunds with no cancellation fee.
I've read so much conflicting information about the issue between the pilots and the airline that I don't know what to believe.
All the other legacy airlines have gone through Chapter 11 in recent years. All had to deal with unhappy unions. None had a strike. All survived (or have survived as merger partners). Only American was never in Chapter 11 until now.
Double-check the fine print on your
trip insurance. With some trip insurance, airlines operating under Chapter 11 are only covered if you bought the tickets before the airline went into Chapter 11.