I'd wager it took a lot longer than that. Several areas in the game feel like they actually take quite some time to traverse, and aren't over and done with as quickly as you play through them yourself. Sanubia Desert for instance I could imagine taking days or weeks to cross till you get to Home. Not to mention who knows how long the Al Bhed took to figure out ancient machina and use them to locate Yuna in Bevelle. Judging by the fact that a wedding had been arranged and almost carried out in the meantime, it might have been quite a considerable span of time.

All in all, it might've been somewhere between 1-2 months, if I had to guess.

Quote Originally Posted by Vyk View Post
Don't forget Sin farted on them an magick'd them to the desert for some reason.
Because that's exactly what happened, right? Sin didn't just, y'know, take them over to Bikanel itself, like it has been shown to be perfectly capable of doing - twice no less - at the beginning of the game.