It turns out the super early morning flight from Cairns to Sydney originates in Japan. Which means that it passes through the international terminal. Which means that at six AM, when it's already over 90 and so humid that your cardboard boarding pass would go limp, if you had one, but you don't, because you showed up at the domestic terminal, you have to run the half mile between terminals, with your luggage, hoping you run fast enough they don't close the flight before you get there. It also means that for the first time since you arrived in Australia, someone asks to see ID before you board the flight. It further means upon reaching Sydney you will clear customs with all the Japanese tourists, and therefore you need real ID, like a passport. Which you left in Sydney, thinking you were so smart not to risk having your passport stolen while staying at a sketchy hostel, or having your passport drown when you are forced to abandon ship on the reef due to a grease fire set by an over enthusiastic apprentice cook. Or some idiot who feels the need to burn incense in their tiny shoebox of a bunk. Or any number of other immensely logical reasons you came up with to leave your passport at home.
What it really means is that there was no reason to get up at the crack of dawn. No reason to skip the last dive of the trip, the one where you finally made it to the best dive site. Which you did because you were concerned the nitrogen you'd built up in your tissues over the last days wouldn't have time to escape before your uber early flight, and then you'd ascend to 30,000 feet and either inflate like a balloon, or worse explode.
Mostly, what it means is that the group meetings that you had promised to attend, the ones you had structured your trip around, are going to have to do without you. While you sit, for seven hours, in the domestic terminal waiting for the next flight to Sydney.