Hello dears

I am trying to book an open jaw LHR-LAX SFO-LHR for some dates in August using the multi-city option on ba.com.

I'm selecting business as the booking class but for some reason every time I search for flights the site is bringing back the SFO-LHR leg in F (A class specifically), rather than J (LHR-LAX is coming up fine).

Anyone else experiencing this or is it just some oddity that's only affecting the moi?

C.