Okay I think this is what the issue is.
Assumption SBR, DPMS, Form I by Homer Simpson

When someone manufactures or makes an NFA firearm using a Form 1 they will put the following in these two sextions.

Box 3.a. Homer Simpson, Springfield IL, 12345
Box 4.a. DPMS, DPMS ADDRESS.

When Homer Simpson goes to transfer it to Ned Flanders, the following is entered for the Form 4.
Box 4.a. DPMS, DPMS ADDRESS

So even though the SBR was really manufactured by Homer Simpson, when it transfers you put DPMS?
I think the NFA BRANCH would be making a mistake, instead the following is what should be put on the Form 4?
Box 4.a. Homer Simpson, Springfield IL, 12345
Box 4.h. DPMS, DPMS ADDRESS