UBL modeling question

[Stephen Green <stephengreenubl@gmail.com>]

Say I did want to add an existing ABIE 'A' to another existing one, 'B'.
Say I wanted to allow for the possibility that it be further extended
so I wrap it in another custom ABIE 'XB' 'container' (as is done with

qualified 'Party' ABIEs in UBL 2 which contain the generic Party
ABIE in such a way that they extend the Party with specific BIEs
like the various 'AssignedAccountID's). How, according to CCTS,
would I name this new container 'XB' ABIE? Would I simply qualify

the contained 'B' ABIE or is that wrong since I am not strictly speaking
merely qulifying the contained 'B' ABIE but am naming a container
ABIE which associates more than just the 'B' ABIE with the container?

What would I call the 'XB' container ABIE which contains ABIE 'B'?
Would I further qualify it ('YXB') to name the resulting ASBIE within
ABIE 'A'?

Sorry if the wording of this enquiry ends up being rather cryptic;

hopefully someone will understand what I'm asking. I think it is
very similar to the naming issues that must have been faced when
modelling the various uses of Party ABIE in the UBL documents. 
---

Stephen D Green