Then:
"In the above exchange, Sydney FIS 5 asks Sydney Air Traffic Control Sector 1 (S1) for an onwards clearance for MDX to enter the Sydney controlled airspace after the Williamtown transit is complete. S1 responds that the clearance will not be available because Sydney control area is not Night VMC (Night Visual Meteorological Conditions - in other words a pilot must fly visually and clear of cloud). So the clearance issued by Williamtown Tower to Sydney Flight Service was never transmitted to the aircraft due to Sydney Sector 1 involvement. As a result, three minutes later at 0856, MDX, with no clearance issued by FIS 5 through Williamtown airspace, tracked from Taree to Craven then Singleton and into bad weather where some 45 minutes later the aircraft crashed in the Barrington Tops."
(Quote from Harry Howard's (former MATC) letter to Channel 7)