What the heck is a NICS "pin" & "upin"? I also don't understand why they need new prints, they already have mine on file from when I got my pistol permit.
The UPIN is the universal personal identification number that's issued once your appeal goes through.
What they'll need is the NTN (transaction number) from the initial form when you bought the gun. Get ahold of the dealer and get that. It should be something like "1G45-AB1."
As far as prints, local law enforcement has them on file from when you got your CCW, but the feds will want a set of their own. Two separate processes.