So does that mean Twohorse Town Airstrip, that has a GPS-NPA mainly because the RFDS fly there, will now become controlled airspace
Yes. (Probably). The endstate has 700ft E airspace over all instrument approaches. The (probably) comes in coz there is some havering about where the 1200ft E corridors will go.
My airspace design
I thought it was Qantas' idea...