@CrazyGrouzin I'm not sure because I don't know how to apply UPDATE.APP to the phone. Can you provide me with a little help on this?
@Lurker I'm planning to send an email to Huawei soon, I'll ask them about bootloader unlock.
extract .zip archive from download
copy the dload folder from archive to SD card /sdcard/dload/update.app
METHOD 1
Settings->Storage->Software Upgrade->SD card Upgrade->Confirm->Upgrade to start upgrade
METHOD 2
power off device
press VOLUME UP+VOLUME DOWN then press the POWER key to enter upgrade mode (keep buttons pressed at least 5 s)
for the bootloader, i have asked huawei and they said bootloader isn't locked