Can you do pro-active upgrades on the BA website if you have a multi-city itinerary?
My LHR-ORD-DTW WT+ booking is teasing me with (obviously wrong) £100 upgrades to CW. If you try to purchase them, then the website throws up a "you can't upgrade this flight online error".
I can understand why the website might not be able to handle this, but it shouldn't really show silly prices, should it?