Although I presume BA will tell you to take a jump or just give you a few Avios to try to placate you, I think you could well have a case to reclaim what you paid via your credit card company by making the same arguments. IMO it's a reasonably clear legal position that if you bought a service based on advertised claims, and these weren't delivered, you should be entitled to a refund. In my experience credit card companies are far more willing to take the side of the customer (it's your credit card company that makes the decision) as you are their customer and they obviously want to keep you.