When I bought (and built) my gyroplane with factory assist, there was no kit. Later on, a dealer in Texas wanted to sell kits, so the factory eventually developed one, but it took time and effort - they had to write detailed instructions, make sure it counted as 51%, deal with packaging, etc. They apparently hadn't done that for the factory build-assist gyros. Maybe their local FSDO was more lenient...? They also counted as light sport, so maybe the FAA just doesn't scrutinize that as much.
Still, I can't imagine Hill is doing this without ensuring he can sell the HX50 because otherwise it's all pointless. (Well ultimately certification is the goal but that takes forever.)