I remember chatting to Peter Nixson, who was their wine buyer years back before they decided in their wisdom to outsource. I asked him about the Concorde wine cellar, specifically the Winston Churchill bubbles. He said the bubbly didn’t last long after the end of Concorde, I can only imagine the rest of it is long gone.
I believe they used to purchase 10-15 years in advance with the Chateaus in France and got them to cellar it until it was ready. Given that sort of timing if they had any outstanding stock it’s probably well and truly gone......... Some of it did, happily, end up down my throat, but that was back in 2004.......