yes its possible. I can sometimes do them, not cleanly or consistently yet...
To exit the top you have to kind of "pop" the nexus up. A tug upward of the top poi will usually suffice for this and then quickly move your hands into exit position.
I'd recommend just starting with horizontal airwraps bottom to top and get those first. The popping motion is similar and will help you to see the timing. Also... this should probably go in the advanced move forum.
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I once learned every move that there was,
Every style, Every technique.
Then I woke up, and forgot it all,
So now I struggle to dream.