Jimmy Cornell's World Cruising Routes on Queensland to New Caledonia advises best times June, mid-September to October and notes:

"this can be a difficult passage at all times because of the certainty of encountering contrary winds for at least part of the voyage, if not the whole of it. It is therefore important to wait for a forecast for westerly winds, which at least will ensure a speedy start. Such winds are normally generated by fronts moving up from the south and the weather associated with them is rarely pleasant. Because of the high proportion of easterly winds in winter it is better to plan this passage for the intermediate season. Similarly, because of the risk of cyclones in the Coral Sea, this passage should not be undertaken after the middle of November or before the end of April."