Ever since UA redesigned their website, if I cancel a booking within 24hrs, I notice my GPU/RPU is never redeposited where it use to be instant. I havent tried this in 6mo so maybe they have fixed it by now. However, I can call the 1K line and they can redeposit it instantly though sometimes it can take up to 20min or so on the phone.

so I wouldn't be too concerned about having to call the 1K line if it is even needed.