I could be wrong, but the trust is only sent to the atf upon a new submission. Other than that, it’s a document you keep and have notarized. I believe it’s a bit of a “loop hole” in that you can add/ remove people without doing anything other than notarizing signatures on the documents. Now if someone is added and you submit a new item on the trust, they have to include everything.Pretty sure you have to go through the entire process to changes trusts, even if you control both trusts. No different than selling to another person.