I moved from Edison to East Brunswick, filled out the proper paperwork to update my FID address and received email stating my updated permit was finalized. I signed up to get a daily email from usps before I moved and noticed the permit was sent to me,  but I never received it (good thing I did because I had proof, they take pictures of the mail and included it in the email). I went to the post office and they were no help. Called the township and I was told that they would need to speak with chief of police to see if I could get issued a new permit, which I'm still waiting for them to get back to me.

Question: Can I sell/transfer my firearm knowing the address has been updated or will the FFL give me a hard time for not having the updated permit with correct/matching address in hand?

If I remember correctly a FFL will not transfer a firearm without matching permit/ID. 

Edit: I completely misread what was being asked. 

You don't need any permit or FPID to sell a firearm.

What PK90 said. Lots of folk forget to include  or don't know about the P like you did (FID). It's FPID, the P standing for Purchase.  Don't need it to sell a legal firearm. 

Understood. Thanks for the information and clarification!