OP here with update: I booked business-class seats to Japan on ANA because we could not find any seats on UA or any other airline to West Coast. Luckily, a relative in Seattle informed us that Japan was facing typhoons, and no way were we going to travel from one hurricane center to another.

We finally were able to talk to a UA agent, and cancel our trip without any fees. Interesting to me, despite the website advisory that the cancel within 24-hours program is only applicable to flights booked over a week beforehand, the agent cancelled our flights and confirmed there would be no cancellation fees. The agent was then able to find seats to SFO, and we booked those. Once again, she said that we could cancel within 24-hours, which would bring us right up to the time of the flight.

Do the experts here find these easy cancellations with last-minute bookings to be typical?

Thanks.