1. Download this UPDATE.APP file and unzip to your phone.s sdcard in the dload directory:
2. Shut down your phone.
3. Power on by holding Power+Vol Up+Vol Down end release all the keys as soon as the Huawei logo appers.
4. The phone will upgrade some files from the file you downloaded and boot into your KitKat 4.4
5. Put your B125 UPDATE.APP in the dload directory of your sdcard. Maybe 1st rename the current fallback UPDATE.APP to e.g. UPDATE.APP.fallback should you ever need it again to downgrade. (here is a very fast download link:
6. Shut down your phone and boot it with the 3 keys (remember to release the keys as soon as the logo appears) to downgrade your firmware.