Why My Phone Keeps Installing and Rebooting after Using the Slow Install of Windows 10?

[Windows Central Question]

Hey Guys. Hope You Can Help Me Out a bit. I own a Nokia Lumia 720. I decided to give it a try to the new Update Windows 10 Mobile throught the Windows Insider Preview. I Chose the Slow Installation and the phone rebooted and it has been rebooting ever since. What can i do to go back to 8.1? or is it never ever going back? Thanks.