Since N isn't an official build and so far has just been a developer preview, I'm guessing not. But once N is released, it will have all those baked in and then updates will be based upon N.
I imagine the April security patch will be incorporated into the scheduled April update for the N preview. That could even explain why Google announced those monthly updates in the first place.
My version of N's "Security Patch Level" is March 1, 2016, so....