<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Gaza:
SYD-Tonga-SYD is a big no, no. Only one International arrival and departure is permitted except travel to/from Papu New Guinea.
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The limits on international arrivals are for the country of origin, not other countries. And since these flights are within SWP, there is no intercontinental arrival issue either.