How long are they going to be gathering feedback? Have an upcoming flight on 18th. Normally I would just ask for a Heineken or tomato juice, but if they are still gathering feedback then I might take one "for the team" and let them know what I honestly think about the new Cava. (Knowing I already did not like the previous one!)
P.S. KL never had champagne in short haul as far as I can remember.... maybe in the 90s?