Based on the route they were taking, I think it's fair to say they were VFR. MB around to Cape Otway then down to King Island. If you were IFR you'd take a more direct route. VFR flights to King Island need a lot better conditions than yesterday's. I wonder, is having 3 pilots on board an advantage or not..? Human factors gurus may be able to comment. Still very hard to understand why you'd attempt the flight given the conditions.