I’m sure this is an easy one, but would appreciate any advice. I had a flight booked using AA miles but operated by BA. I received notification 13 days before the flight that it was cancelled and I saw that I had been rebooked onto an alternative flight a couple of days later. I spoke to BA asking to be rebooked at a later date under Art 8(1)(c) but they said I would need to contact AA as they issued the ticket. I spoke with AA and they say they can’t do anything as there are no award seats available around the date I’ve asked for (although revenue tickets are available in the cabin booked). My understanding of EC261 is that it’s the operating carrier (BA) who is responsible for rebooking, not the marketing carrier (AA) - is this correct?