Earlier this year we flew from IAD to LHR. Spent an number of days in London then flew RT London to Prague. Spent one more night in London & flew LHR to IAD. This was all on one ticket. At the time we booked the tickets it was cheaper to book all flights on one ticket rather than 2 separate tickets.
The problem I had in booking all flights on one ticket was trying to upgrade just the transatlantic flights to WT+. We saw no reason to upgrade the rt London to Prague because it was such a short flight. And it was very expensive to upgrade all 4 flights.
I called BA & they couldn't help. They told me to check at the airport & perhaps an upgrade would be available on the day we traveled. Fortunately, we were able to get upgrades for both transatlantic flights.
This year we plan to visit London & Budapest so the situation is very much the same. It's too early to book our flights but I am checking prices often. But I really want to book WT+ up front & not have to worry about getting an upgrade at check-in.
I have 2 questions. Is there something I'm missing in booking a multi-clty flight where I can upgrade just the transatlantic flights to WT+?
Is there any reason why I shouldn't book on 2 separate tickets given that there is minimal dependency on making connections? We will be in London 10 nights before our flight to Budapest and another night between arriving from Budapest & leaving for Washington.
Thanks so much for your help.