Ann: Quarterly Activities Report, page-21

I can only conclude that you're looking at AUD whereas I'm looking at USD. The main profit contributor to RSG (until now) is the Syama mine, where costs and revenue are in USD. The comparison to last quarter's numbers on just AUD alone is not telling the full story. The company has changed its FX basis to 0.81USD/AUD from 0.75USD/AUD.
What I see is on USD terms, the AISC has increased (and if you want to compare RSG to other goldies in the world, typically people will normalise to USD basis comparison). By making AUD stronger (0.81 instead of 0.75), effectively the company is making the costs in Syama lower in AUD terms (quite smart to do this accounting change eh?!). So, on a cost implication in USD terms, since the company has committed to deliver ASIC of US$960/oz, what I said earlier still holds, i.e. the company needs to produce at significantly lower AISC in the remaining 3 quarters in order to meet the FY18 guidance.