Hello - apologies in advance - I have searched the forum and cannot find the answer to this though I imagine the issue is my search skills.

I am looking at BA.com at SFO --> LHR --> FCO. From SFO to LHR, first is available, but of course from LHR to FCO that's only Club Europe. The BA search tool shows me the seats in F if I search the flight legs separately, but if I search from SFO to FCO via LHR, it shows only business. Can a booking like this be performed online or do you need to call?

Thanks much