Question about fare codes and availability
 

TG shows following availability for First class for a flight in Jan:

F4 A4 P4 (I believe all 3 are first class fares?)

Now, does this mean there are a total of 12 seats available in F?

However, the aircraft is an MD-11, which has only 10 F seats??

What is wrong here or I am missing something?

No, from that display you cannot divine any more than that the airline is prepared to take reservations for 4 more first class seats, in any of those first class booking classes.

It literally means no more than that. It may be that the cabin is empty, but the maximum display is 4 seats. Or the cabin may be fully booked already, but the airline is prepared to overbook by another 4 seats. That's how little GDS displays tell you about the actual booking levels on a flight.

Most likely 4 available seats. There are 4 available "P" fares, but they will sell you a F or A fare as well. Someone else can probably explain it better, but basically, if there is X number of a discount fare code, there will be at least that number in full fare seats, and any fare code in between.

Edit: to add that Globaliser is correct, in that the correlation between fare bucket availability and actual number of empty seats is often weak.

They are different categories of first class fares/buckets - the same way Y, B, M, H, Q, V, W etc are different fare classes/buckets for coach seats.