OPC = Operator Proficiency Check. It basically is a Command Instrument Rating Renewal with some extra bits thrown in. I definitely don't have the impression that it is a chopping exercise. My understanding is that only a VERY low number of pilots don't make the grade here. I have also been told (straight from the horses mouth) that if performance during OPC is not to standard, you
may be offered another crack at it after some more training.
All the operators in Australia need pilots at the moment and they're not out to get you.