Guarantee's? Absolutely none. If you know for sure you have gone to Android 5.x then keep updating. To know what
Android version you are at go to Apps/Settings, scroll to bottom and read Android Version. If you have already upgraded to a version of Android 5.x.x on your Verizon Droid Turbo phone there is no way to go back. Many users
on this VZ forum encourage users to just jump in on the Android upgrades Big mistake. Perhaps Motorola.com support
forums for the phone may bail you out right now.
If your Droid Turbo is under the 1 year Motorola warranty then call them. In the USA at 800-734-5870. There are several types of phone "Resets".