Point of Contact (POC) states comply with their State Bureaus of Investigation/State Police rules for information.
Federal NICS info is much more limited than the 4473 info collected.
The NICS info only has to be the same as is on the Prohibited Person list that NICS actually is. And it's only retained--as our esteemed
@dogtown tom points out above--for the length of the check.
If curious, the number of checks can be found tabulated here:
https://www.fbi.gov/file-repository/nics_firearm_checks_-_day_month_year.pdf/view
So, for 01 September of this year there were 88,568 checks performed. While storing data is cheap, it's not unlimited.
Well, Welcome to THR, again