I got that, I was just under the impression that if you put a rifle upper on it that is too big for it to be shot with one hand easily then it would show intent to shoulder it even with the brace and they would then classify it as a rifle, and once a rifle always a rifle. After looking it up, the once a rifle always a rifle part is wrong, as I posted from the ATF website. However, with the new rules (should they actually pass muster) they would probably classify it as a rifle as long as the rifle length upper is attached, but there is nothing wrong with converting it back to a pistol, so there should be no worries keeping the original pistol length upper. If the once a rifle always a rifle bit was true, then you could get into trouble keeping the short upper unless you had another lower that was a pistol lower or an SBR lower. But it's not true, so he would be free to switch it back and forth.