Oh, I think in this case you would not be allowed to cancel the initial reservation. You have doubly bound yourself to receive the service by getting the park reservation and the ILL, like how you agree to ride DC metrorail by tapping in then boarding a train, or ordering food from the chick fil app and checking in at the drive thru. If Disney can't provide the service at your scheduled time, that is the first time they should provide an off ramp to back out of the transaction. If you agree to an anytime return ticket, as long as the ride is operating at some point the rest of the day, no refund.