Xiaomi Mi A1 starts getting a new software update with build number N2G47H.7.12.19, but unfortunately this is not Android Oreo update as expected. The Android 8.0 Oreo update probably will hit the phone later this month or early 2018. The new update only includes general bug fixes, stability and performance improvements. Also, this update maintains the previous December 2017 security patch level.
Xiaomi starts rolling out the N2G47H.7.12.19 OTA update for Mi A1, which weighs around 63.4MB. Since the OTA (over-the-air) update is rolling out in phases, it will take few days to get it on all devices. If you cannot wait for OTA, you can also download the firmware and install manually.
As said above, the update (N2G47H.7.12.19) is still based on the Android 7.1.2 Nougat and does not include any major features. However, all users are recommended to update to this version, as it may be a preparatory patch for Android Oreo, as it has newer Kernel version.
Update: As said above, N2G47H.7.9.21 is a transition version for Android Oreo. All users should update to this version to get the Android Oreo OTA update.
If you have not received the new software update, just go to Settings > About Phone > Software updates. If update available, it will start downloading the latest update automatically.
For your information, Xiaomi already started Android Oreo beta testing in Mi A1 and promised that the device will get Android 8.0 Oreo update before the end of the year 2017.
How to download and install N2G47H.7.12.19 OTA update on Mi A1
– Save the OTA update on your phone, boot into recovery mode, and select apply update from sd card.
– Choose the ROM zip file to flash it. Once done, your phone will reboot.