Stevie
Do a search on MFU (Miles for Upgrade) or look in the sticky thread at the top.
Basicly you can't UG from WT-NCW form the US as a UK member for a couple of reasons.
1. One class upgrades available only so WT - WT+ and WT+-NCW NCW-F and WT-WT+ would be 25k Rt and the same for WT+-NCW
2. MFU have to be booked at the time of booking direct with BA only so not through a TA.
3. MFU can only be done departing from the country you are registered in. (As it turns out this could be total cr@p

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CT