Huawei Mate 10 starts receiving Android 9 Pie update, huge download size9
Mate 10 devices in Europe, but other regions are likely to follow soon. One thing worth noting is that this is an unusually large update (nearly 4GB!?), so make sure you have enough free storage on your phone.
We're not sure what security patch is included in the update, but expect many visual changes since EMUI 9.0 is replacing the previous user interface. Those who've been in the beta program and got to test the build probably know what to expect.
At least nine Huawei and Honor smartphones have been confirmed to receive Android 9 Pie updates: Huawei Mate 10, Huawei Mate10 Porsche Design, Huawei Mate 10 Pro, Huawei Mate RS Porsche Design, Huawei P20, Huawei P20 Pro, Honor 10 (Honor View 10), Honor V10, and Honor Play.
source: XDA Developers