JF denotes Joint Fighter. I am hoping Project Azm will be PF-1 or P-1. P-1 has a nice ring to it.
defence.pk
"Someone may or may not have seen project AZM design
I can say with 80% confidence that what I have seen is indeed AZM design. I've debated in my head about it and I have decided not to disclose anything about it. I will let some idiot do that when it becomes more widely known. I will only say this: It is a clean sheet design. Now whether Pakistan uses this design to get concessions on J-31/35 is anybody's guess."