The rule is the following:

113N . 4. TRAVEL MUST BE IN A CONTINUOUS FORWARD
114N . DIRECTION BETWEEN AREA 1-AREA-2-AREA 3.

(IATA Area 1 is North/South America, Area 2 is Europe/Middle East/Africa and Area 3 is Asia/Australia).

But that rule doesn't require that all travel in the area of origin be completed prior to leaving an area. What it does prohibit is re-entering an area after leaving it; but the area of origin is required to be re-entered (as the fare must terminate in the continent of origin, and in fact in the country of origin except as allowed by the listed exceptions in the rules). I interpret that to mean that with an Asia origin you can do Australia either first or last in the routing (but you couldn't do ICN-HKG-JNB-SYD-LHR-JFK-HKG-ICN for example).