I'm searching for F availability from JFK-HKG late March (Already have 2 J seats booked) Searched the other day for F and when searching for 1 passenger, it shows availability and says "5 seats left". I then search for 2 passengers and it shows no availability. I ran this search on BA and QF sites, same results. How risky to try to upgrade one to F and then attempt the other? I have a feeling that BA is showing some phantom availability and I'd be out of luck and in a worse position than just keeping the J seats as is. Any thoughts? Thx.