As a data point - Flight JFK -> MIA / MIA -> JFK booked in January 2020 so before the new regulations of time changes for refund, flight was moved by approx 2 hours. Called up about 2 weeks ago and was assisted by a very friendly customer service rep. Walked me through what I would have to do, he cancelled the flights as saw the time change so that i could request a refund on the prefunds site. Was on "pending review for and on Thursday this week money already back in my account a few days ago.
Great service I have to say.