Here’s How You Can Roll-Back to CyanogenMod 11S From Cyanogen OS 12 On OnePlus One
The Cyanoegn OS 12 is now OTA after being held back due a missing OK OnePlus feature. The build brings some needed fixes in addition to the voice command functionality, and takes the build version to YNG1TAS17L.
However, if you wish to roll-back to CyanogenMod 11S for some reason, here is a guide that will help you do that. Keep in mind that the process will wipe your data and restore the device to CyanogeMod 11S firmware. So creating a back-up is the safe option.
Step-1: First, you must download the appropriate stock fastboot ROM file for your OnePlus One from the link provided.
Step-2: Now Unzip the downloaded file and put it on your desktop.
Step-3: Boot your device into fastboot mode, after which you should disconnect the phone from the PC if it is connected, and switch off OnePlus One. Hold Volume Up and Power simultaneously until the fastboot menu appears on the screen
Step-4: Install ADB drivers if you have not haven’t already.
Step-5: Download one of the following zip files based on the storage capacity of your OnePlus One phone
Step-6: Unzip the file and copy it to the same folder where you have saved the stock ROM. Run the file now
Step-7: The script will unlock the bootloader of your device, before installing the CyanogenMod 11S file. Follow the instructions.
Keep in mind that if your phone reboots after unlocking the bootloader, simply disconnect the phone from the computer and enter into fastboot mode once again.
Step-8: The script will do the rest, and will continue installing the CM11S.
If you have any questions, let us know in the comments.