the worry for me was 3rd and 4th operating costs, and from the table they provide, we can work out that OGC have had two straight quarters of total operating cash costs of AUD$800+/oz... 3rd quarter ~A$812/oz and the 4th quarter ~A$833/oz.
Cost increases from ~A$590/oz to ~A$833/oz have probably had a big part to play too in today's fall.