Yes it is included. There are warning boxes throughout the tutorial (towards the last steps, basically) where they tell you that if you skip such step you'll lose the data, and they also recommend that you backup certain files on your computer and stuff. If you follow every single step in the tutorial, the backups/restores will be included and no data will be lost, really. And even if you do happen to lose something, some of the things might be recoverable from the SD backup you might wanna do before starting the hacking.