@dhdunbar, can you provide the CFR, industry circular, or policy statement for this? I'm working with our internal counsel on a similar issue and she doesn't really care for it when I say, "Hey, I've read on the internet....". I've seen this:
https://www.ttb.gov/ponl/ref-guide/03070.html
But I can't quite tease out in 27 CFR. Maybe 19.54/55? Any pointers appreciated.
Edit: I think I found it in 26 U.S. Code § 5178