A word of warning for anyone who booked this ticket through American Express Travel: I just got charged £2,726.30 for these flights, even though I received a confirmation and eticket with the "correct" £772 price. A couple of hours after I received my eticket, I received an invoice for £2,726.30 (which I did not notice until I saw my credit card statement today).

Ironically, American Express Travel blocked £772 on my card initially. They then cancelled this and just charged the £2,726.

I'm going to have a little word with them tomorrow. Quite interesting that they think they can just charge someone for almost £2,000 I never authorised.