<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by LHRtoORD:
1) you can't go back through SYD -- once you're there, your tour is over. Better SWP sector is (HKG-)AKL-MEL-PER-CNS-SYD.
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I don't think there is a direct flight PER-CNS. However, you could do PER-DRW-SYD and actually get a few more miles than going via CNS.
Now the bad news: you will get no credit for the CX flights unless you have a Canadian address on your AAdvantage account. OWE economy is booked in M class and CX does not give credit for M. Also, QF only gives 70% credit.