Strictly speaking, even H3 - from a dynamic perspective - is not nondual (in any absolute sense).In a relative (dynamic approximate) sense it is nondual with respect to its state aspect. However with respect to structures it always remains dual. However because these structures are bi-directional and paradoxical, phenomena ultimately become so transparent and fleeting in experience, that they do not even appear to arise.
However - as always - it is important to preserve both state and structure aspects (as emptiness and form) even in this most contemplative stage of development.