Party Mode Multiroom?

I cannot find how to select Multiroom mode in the newest nStream app.  I can use the older version of nStream on my iPad to select Multiroom from among Inputs on my NDX.  When I do, the new nStream on my iPhone tells me my Qute2 is using the NDX as Multiroom source, so I guess it still works, somehow.

The Knowledge Base searches I did on "party" and "multiroom" find "How do I play Party mode/multiroom?"  Answer:  "The linking of multiple Uniti or ND series products for synchronized multiroom playback is not supported at this time.  However, our NaimNet product offers that functionality - and much more.  Please see www.naimnet.com for details."

Surely, Naim are not dropping support for this recently-added feature. (?)

Nick