Does anyone else think that teleporting the entire Shinobi Alliance outside the barrier is a double edged sword.
Earlier Madara remarked that it would take time to get the moon into position before they could cast the genjutsu and Obito has been focused on clearing the battlefield despite being the Ten Tailed Jinchuriki.
So maybe he has to maneuver the moon into a position where he can cast the Infinite Tsukuyomi on the entire world and he would have to wait as the moon moves.
My theory is that now that the barrier is up he basically has time to start the moon's movement and that the alliance has to get back in to beat him before he gets the moon into position.
Sort of a count down until destruction thing kind of like in DBZ where the fight with Freiza had the five minutes before the planet exploded.