Well, your second post was 18 hours after your first post. So did you get an answer from Chase or not? Or did you give up staying on hold? Or are you still on hold after 18 hours?

I don't see why you started this thread while you were on hold, waiting for an answer from Chase. It might make sense if you got a "no" answer and you would want to know if it was worth HUCAing, but if you got no answer at all, why not wait until you get answer to post?

I'm guessing that very few FTers have actually tried this, so most people who see your past have no experience with the issue, and can only guess.

In general (not UR specific), depending on the reason for cancellation (having found a better rate at another hotel is not a great reason), you may get better results calling the hotel directly, rather than calling the booking company. But in that case, if the hotel does agree to cancel the reservation, how/do they notify Chase so that your points can be reinstated?