Complex sentence: Billie and Christy have managed to turn everything around: while the two of them are now at the Manor and demons are at Magic School, the Charmed Ones are forced to hide in the Underworld.
Split into simpler sentences: Billie and Christy have managed to turn everything around. While the two of them are now at the Manor and demons are at Magic School, the Charmed Ones are forced to hide in the Underworld.