FWIW, local FFL shipped records back to WV, needed to retrieve serial number for a gun, local PD filed a request, crickets. Local PD didn't give a . . . hoot, and ATF cared even less, Needed one digit from the Serial No.
The paper ones stay onsite until biz closure, then they are shipped to the FFL Center in Martinsburg, WV (the same folks who do traces).
Why all the discussion from the junior G-men about guns being traced back to them makes me laugh.