According to Flightaware, this flight flies from SYD to SW over high latitudes > 55º (and on Dec 27/28 even over 60º ). I understand when westerly winds blow on the great circle route an escape to a bit higher latitudes (why not lower e.g. MRU and Rodrigues) is feasible but so far south ? Very remote to the inhabited world, when an unlikely event such as an emergency landing on sea should occur, the location is hard to reach.
Or are the track logs of Flightaware unreliable ?

The return flight QF64 flies on a less southerly route but it has a tail wind as it is eastward.