* The stock ROM has firmware and configuration settings which is not included in the /e/OS ROM. These files are required for the hardware to work correctly. By flashing the stock your smartphone is optimized to receive this operating system update. This will be a one time process and subsequent /e/OS updates will be available OTA (over the air).
* Flashing the /e/OS upgrade directly without flashing the stock ROM can result in the device going into a bootloop.