Google nearly three weeks ago released the first Developer Preview of Android O for the Google Pixel and Nexus devices. However, it will take ages for OEM's to out the next iteration of Android, but it's surprising how Huawei managed to port the latest OS.
The report further says that the phone is running rooted version of the Android EUI, but the phone is not usable as a daily driver as it is plagued with issues related to Google Play Services and Wi-Fi.
One of the prominent features in Android O is the picture-in-picture mode, and the feature is reportedly working fine in the Mate 9. So, will Huawei manage to release the Andriod O before Google does? Time will tell.