I’m sure this is a major no no, and I am just curious, because I don’t want to miss out on the upper sale at BCM. I have also seen alluded to that folks had the uppers before they had their stamp back.
Can I order an upper before my paperwork is back (it is in right now). If I can’t have it at my location, can I send it to siblings house that is 200 miles away?
I just want to make sure I have the guidelines correct…
yeah, i saw a $385 12.5 upper at BCM this morning, that i almost ordered. i have sent off for a SBR stamp, but it will be awhile before i get the paperwork back. i thought about ordering one, and stashing it at my sisters place, until my stamp comes in. so—what say yall???
that is the exact one i was looking at…itching to…pull the trigger, so to speak, on that one. 
Seems reasonable to buy the upper and store it at someone elses house. If you are really paranoid have it shipped directly to them in their name.
It’s really a judgment call on your part.
As long as that sibling doesn’t have any regular Title I (non-NFA) rifles or lowers laying around, then that would work fine.
Out of my lane here, but if you have a pistol lower, wont that work?
A pistol lower should work as well.
I just stored my upper at my in-laws house, simpler in my odd case.
The same thing happened to me years ago. I bought when there was a good deal on colt commando uppers. It’s not a per se violation of the law, but if you are giving ATF a reason to want to squash you, they could stretch things.
I had mine in my locker for a year before I got around to registering my lowers. No one will ever know or care, but each individual has to know what he is comfortable with.
This has been discussed numerous times in this forum. Please look around.