Xiaomi has rolled out the first Mi phone powered with Google Android One. Unlike any other Mi, Redmi, or Redmi Note variants, the Mi A1 is not running MIUI but the stock Android ROM. All parts of the operating system is designed, made, and created by Google while phone manufacturers provide the device. Generally, Google manages and handles all aspects of the OS including Security and system updates. However, this is not the case for Mi A1 which is handled by OEM.
Android One was launched by Sundar Pichai, Product Chief & Designated CEO of Google. It has been noted that the initiative was created with Indian market as the basic standard.
Generally, when a new version of Android One is released, Google will push the OTA update. This means that you can easily update the operating system of your phone easily. Over The Air (OTA) update mechanism allows you to immediately download and install the update within the system.
However, in some cases you might also need to keep a full package of the software in your computer. This will be useful especially if you want to unbrick your phone or to reset your device into its default state.
You can grab Android One for Mi A1 Fastboot ROM having version N2G47H.7.10.30 which is based on Android 7.1 Nougat from direct link below. The link supports multiple and resume-able connections. Please keep in mind that the Fastboot ROM below is only for Mi A1 codename Tissot.
The file is original, intact, and untouched. You may need Mi Flash tool to install the ROM above onto your device. Moreover, you have to firstly make sure that the bootloader of your phone has been unlocked officially or otherwise it will fail.