Anything is possible on the TBC. While we know there are 12 legs, we've been assuming that means 12 episodes and 12 hours. Till we have the schedule information fowards the end of the season, we won't know for certain.
And I do believe this is the first time, ever, that the show has confirmed an extended pitstop well more than 12 hours, or even more than 24 hours,much less a task based extended pit stop. Very different, very interesting, and very humanitarian.