The episode order apparently is for 12 episodes, which has been the norm since TAR 14, IIRC. I think the operating assumption has been that there will only be 11 legs because of the first leg being an uberleg (TBC) over two episodes.
From the fact that there was a start line task, the problems for the one flight from LAX to Sydney via Hawaii and one other unscheduled stop, and from the extensive spoilage information about the Sydney portion of the leg, I can see a 90 minute or 2 hour premiere just for that. It is a lot, but it does seem to me that eventfulnesswise, this has to be one of the most front-loaded first legs ever for TAR. And of course, CBS and WRP will want to make every use of the HD cameras focusing in the locales in the process. But we'll have to wait and see.