ParisHiltons, perhaps I have not explained my point clearly?
The Sydney ATC system has, this morning, suffered (another) failure to which the ATC response has been to reduce the volume of traffic so as to restore a level of safety.
Now consider the situation that had the fault (whatever it was) happened at 0820 instead of 0520, with maximum aircraft in the airspace.
By definition, in the period between failure and the reduction in traffic being achieved, there would be more traffic in the air than could be safely handled with the reduced functionality available to ATC.
IF THIS STATEMENT IS NOT TRUE, WHY REDUCE TRAFFIC NUMBERS?
Airervices are meant to maintain a safety management system that precludes this happening and CASA are meant to oversee the validity of that system.