It is hard to know what the mining cost will be at this stage, but in the last announcement they were talking about being able to use larger and more efficient equipment as they can run wider ore drives. You are moving more rock, but with larger equipment so it is a bit of swings and roundabouts. My guess is we are going to see a new cutoff around 2.5g/t which is still going to make a massive difference to the MRE.
Where the real saving will be made is on the capex of the plant.