You'll have to bounce in via one of the mainland hubs - probably Sydney, seeing as that's where MLCMM and co will be coming from. It's a 23 hour flight from Londinium ... I'd not leave Europe any later than the Monday. With time differences that puts you in Aus sometime on Wednesdsay. You could cut in finer, but I can't see why you'd want to. We'll need to get into Taz on the Saturday (early-ish flight).
Besides, no amount of time will prepare you for running 13 miles up hill into a blizzard.
You will at least have the advantage* of not having done so before
*ignorance is bliss