https://wccftech.com/android-pie-rolling-out-for-the-huawei-mate-10/

Android Pie has been around for over two months, but not a lot of devices got it officially. Chances are, there is already a Pie-based LineageOS for most devices, but that isn’t for everyone.  Following the footsteps of OnePlus, Nokia and Sony, Huawei rolled out Android Pie for the Mate 10. Huawei has already been operating a limited Android Pie-based EMUI 9 beta program since last month for many smartphones including the Huawei Mate 10 series. Huawei also recently unveiled some region specific “Made for India” features in EMUI 9.

The update has a download size of 3.94GB, which is unusually large by Android standards but regular in the Huawei ecosystem. EMUI 9 brings a streamlined UI and support for most Android Pie features. It also brings a new gesture navigation system. Interestingly, EMUI 9 is a hybrid of EMUI 8 and stock Android Pie. The UI has been significantly updated in terms of the aesthetics of the quick settings menu, but other aspects such as the status bar remain unchanged. EMUI remains one of the most heavily-customized Android forks and might not be for everyone, especially users migrating from stock Android devices.