It's all the same thing.
If you take a Ruger 10/22
rifle action and put a 10" barrel on it, it becomes a SBR. You're asking for trouble unless it's reregistered as a pistol and the paper work is done through the BATF. The stock won't make any difference. It's still a SBR. If you cut the barrel down to 16", it's still a rifle.
No different than taking a rifle action and using it to build a pistol. It's the barrel length and OAL that makes the difference.
Clear as mud huh? ??? :

The "shorter than 16" are the key words.
Any length rifle barrel on a pistol action is OK. (Remington XP100)
Look at one and tell my how you can tell the difference?
The Ruger"Charger" is marked as such. The Charger is a pistol even it the BATF doesn't know that.
And, I will be really surprised if you hear back from the BATF tomorrow. You may, but I'am thinking it will take a bit of time.

Keep your fingers crossed for a speedy reply. ;D