HOTA or Huawei-Over-the-Air is the standard official OTA update pushed via Huawei servers.This is the type of upgrade typically released for every Huawei smartphone in Europe.
FOTA or Firmware
FOTA stands for Firmware-Over-the-Air and is the same as HOTA. In this case, however, the software release servers can be hosted via third party companies, such as network operators.
It is not a common practice for Huawei.