Charlie 32- Are you an actual Gold/prem card holder with Ba or are you using that moniker. If you're the former they really will listen to you.
However, I must go back again to the point that they owe NO duty to anybody, irrespective.
Did Sabena owe a duty to anybody that stopped it from collapsing? Did BMI owe a duty when all its ops at EMA became loco.
If you're not happy then you're the king, take your business elsewhere, brits have never had it so good with regard to choice in the wider passenger aviation market, one of those choices happens to be BA, where often the price is right, or often they seem mad to be charging what they do!
Where all this duty is coming from, i don't know, but it doesn't belong in the aviation business, they only owe you a duty once you have decided that they are worth spending your cash on, a duty to get you from a to b (or in the regions a to b via c!)