My later thought on the A21NLRs and LHR is that it's quite usual to have twelve rows of business on ATH-LHR meaning 48 seats and it's usually full. There is no way these new planes will have 48 business seats and so if they were to be used, there would be insufficient seats to sell at business fares but crucially, on longer European routes, the new planes would have to remain interchangeable with the existing fleet. On the other longer routes I fly from ATH, HEL and DUB mostly, there are often only three or four rows of business, sometimes less and so maybe if the planes were to be used in Europe, it would be these routes and not LHR that might see them.