The thing is that the difference would depend a) when you both initially booked and the taxes and yq at that point b) when you made the change as again there can be difference in yq and tax.


If im honest its quite often the case that between World traveller and world traveller plus there is tax/yq difference on o/b flight from UK but on i/b from USA then no difference. I cant remember having seen the same for WTP and club though.