From the press release:
Knights of the Fallen Empire marks a renewed focus on BioWare-style cinematic storytelling in Star Wars™: The Old Republic™. Your character will become the Outlander, a veteran of the Great Galactic War who comes face-to-face with a new threat to the galaxy: the Emperor of the Eternal Throne.
This expansion also raises the Level cap to 65, and includes the option to create a Level 60 character! This allows you to start fresh in Knights of the Fallen Empire and jump right into the new story content. We are also delivering this story content in a way never before done in Star Wars: The Old Republic: Chapters. The first nine Chapters will be available at launch on October 27th, with new Chapters delivered regularly following that.