Were there any proposed restrictions on types of buffer tubes on pistols without braces?

None of that matters at this time, but when AFT was publishing all the "criteria" for their ban there was a mention of buffer tube length not being any longer than necessary for function of the firearm.  Their point apparently being it would be an aid to shouldering.  I have a 9" round tube on an "other" or "firearm" purely to make my 10.5" gun's OAL over 26" for addition of a VFG.  Prior to the injunction, under AFT's directive, I would have had to disassemble that rig.  But, for now, she is still intact.

The directive called for removing the brace, but you could keep the carbine buffer tube as is.

Thank you, what I was looking for.