Complex sentence: On, it was announced that all six films in the series would be stereo-converted to 3D and re-released in episode order, beginning with "The Phantom Menace", which was released in 3D to cinemas in February 2012.
Split into simpler sentences: On, it was announced that all six films in the series were supposed to be stereo-converted to 3D. They were supposed to be released in episode order, beginning with "The Phantom Menace", which was released in 3D to cinemas in February 2012.