YSMB is 4.9nm from CALGA NDB almost due east, 15nm+ from LANOL. CALGA Holding is to the west of the NDB. Same block of airspace as WVA.
The only traffic within 3nm of the airfield is either local guys, monthly gas pipe inspections or an occasional stray heading to BROOKLYN for VFR lane to BK. The field is too scary for the BK schools... for the most part.
I can count the number of aircraft on a busy day with one hand.
The guys were jumping all day Sunday, about 8 or 10 loads to 10k with no problem from ATC or area traffic. Something happened between Sunday and today in STC.
IFR traffic very rarely if ever gets within the vicinity of the aerodrome. The heli does a climbing circuit, essentially within the confines of the circuit area.
Tyler: Are you a Sydney ATC'er? Then you would already know all of the above.
Wollongong, Picton, WVA, Wilton, all these dropzones are as close or closer to routes, reporting points, etc as Somersby. In BNE they drop 9nm from the terminal! What is so special about this situation?
Well, it appears that someone has done a little more research and has more airspace knowledge than: Tyler (Billy Bob) Durden
A basic understanding of the airspace you are offering an opinion on would help next time.