Now here is an interesting question>

Say you are running PT 10/110/12 on a new Macpro trashcan.
Your sole IO is UAD Apollo duo and using it’s plugins.

Then, you need to employ a different ( non UAD ) interface, like the MOTU 16A in my situation.
As well as a copy of Nuendo 5/6/7.
Can you still have access to the UAD plugins :
A) when you boot into PT with the new interface
B) or…boot into Nuendo with the new interface

I will soon need to face this situation, and would very much like a qualified answer.
Budget and decisions will depend on this very question.

I imagine it would work if you created an aggregate device on the Mac that uses both interfaces. john.