I have seen the RAAF park the aircraft when they couldn't meet curfew. I have never seen RAAF VIP fleet arrive or depart in breach of curfew. I do recall a C130 landing at Sydney during the curfew after declaring an emergency (which is permitted in the legislation).
I think the fines were significantly increased after a SE carrier elected to depart. It was Mardi Gras so no accommodation was available, cheaper to pay the fine...
Missy (missing you already)