https://www.androidsage.com/2016/04/21/install-huawei-ascend-mate-7-android-6-0-marshmallow-b522-official-ota-update-download-mt7-l09c432b522/
Install Huawei Ascend Mate 7 Android 6.0 Marshmallow B522 Official OTA Update [Download MT7-L09C432B522]