Originally Posted by
Anonba
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.
WT to WT+ there shouldn't be a YQ difference between outbound and inbound, and the YQ for WT and WT+ should be more or less the same.
There is a tax difference between WT and WT+ due to APD. For example APD in WT from LHR-JFK is £69, but for WT+ it is £138. APD is only payable for leaving the UK and not arriving, so the extra APD would only be charged if you did a UuA from WT to WT+ on the outbound from the UK. If you just UuA the inbound from WT to WT+ from the US back to the UK there is no extra APD to pay.