We had to cancel our Dec trip because of the timing of finalizing our daughters adoption. I called and they were very understanding and refunded our tickets. He did say it was a one time thing. I don't know if they can see the many MNNSHP and MVMCP we have been to and never cancelled, but he was very kind. I will say I was not expecting a refund and I didn't ask for one either. Hope you have a safe surgery and a speedy recovery.
DH had a ticket to MNSSHP but was very sick and did not go. That night, I went to Guest Services at MK and explained the situation. They refunded our money.