Evidently I read a White Paper not to be confused with a "Letter".
As I said before I don't have a dog in this race but if I did I'd be absolutely sure I knew what the law entailed. And I surely wouldn't take some internet guys (me) word for anything.
ATF - Paper
https://www.atf.gov/file/11816/download
Leaked White Paper -
https://d3uwh8jpzww49g.cloudfront.ne...-or-modify.pdf