LucasFilm announced at Star Wars Celebration VI today that Star Wars: Episode II - Attack of the Clones and Star Wars: Episode III - Revenge of the Sith will be re-released in 3D just one month apart from one another next fall. Take a look at the official statement from the Star Wars Facebook Page.
"Breaking news from #StarWarsCVI: Attack of the Clones and Revenge of the Sith to be theatrically released in 3D back-to-back, September 20, 2013 and October 11, 2013 respectively."
It was previously believed that these new 3D versions of the prequels would be spread out over the course of three years. Star Wars: Episode I - The Phantom Menace hit theaters in 3D February 10. It isn't known when the original trilogy - Star Wars: Episode IV - A New Hope, Star Wars: Episode V - The Empire Strikes Back, and Star Wars: Episode VI - Return of the Jedi will be released in 3D.