Hadley Rille
Provided that the aerodrome remains licensed and the length of the longest runway stays the same the current 2.5 NM radius ATZ remains in place.
If the aerodrome was to de-license, it could keep its ATZ if either ATC or AFIS is provided. However if the main runway length is reduced to 1850 metres or less, the ATZ would reduce to 2.0 NM radius. If only Air/Ground Communications Service is provided, they would lose the ATZ.
Interesting times ahead, if the aerodrome cannot operate as a viable business with passenger carrying flights, it certainly will not without them. The infrastructure necessary to support passenger flights (ie ATC/ ILS/Instrument approach procedures) will not be sustainable.
Sorry to say it looks like the end of the road for the airport as we have known it for the past years. I shall be sorry to see it go as I had my first ever flight from there, age 4 years, in a DH Dragon.