An update to my situation where I've been awaiting a 2-4-1 taxes refund since April worth approx £1400.
I was assured that BA processed the refund on 12 May, but AMEX tell me today (22nd) that there is no sign of it and it has not been credited 10 days after it was allegedly issued.
I am giving it one more week then I am going to enter dispute with BA as there is no sign of a refund on my account.