This OTA can only be installed on MT7-L09 Ascend Mate 7 variant already running the C900B331 Lollipop firmware.
The device needs to have the stock Lollipop recovery and the system should not be rooted/modified.
Make sure there’s more than 40% charge left in the battery.
Step 1: Download “update.zip” OTA package from the mirror provided above.
Step 2: Create a new folder named ‘dload’ inside the top level directory of your Mate 7’s microSD card.
Step 3: Disconnect your device from the PC when transfer completes.
Step 4: Open the Updater app, tap menu, select Local update, choose the update.zip package and confirm its installation.
Step 5: [Manual installation] After copying the OTA package, turn your phone off and reboot while holding Vol up + Power till you enter the stock recovery. Select apply update from SD card, choose the update.zip package and flash it.