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. Tony knows the Indian Ocean backwards, (if he is not there "Kat" is also great at helping).
Now, what worries me is you are planning to head across the top of OZ.. difficult to say the least. Unless you plan on motoring all the way.
The wet season is from Nov/May. That means you are in the cyclone season. The dry season is May/Apr and that also means Easterlies across the top of OZ and in the northern Indian Ocean... not good.
Understand what you have in mind, but I say don't do it, go the longer way (quicker in the long run) around and head to Freo then across the bottom of OZ to Melbourne/Sydney /Brisbane.
Lets see what others advise.