IndexError: list index out of range while deploying new rack

In order to subnet the datacenter v4 networks for each rack environment, NetworkAPI gets environment configuration from ip_config and EnvironmentConfig (populated by datacenter feature for the room).
While deploying new rack, it is trying to statically allocate /18 network for the rack (networkapi.api_rack.facede.py:664 - "prefixo_inicial"). As such, when the environment is configured to smaller networks, it is raising an error index out of range error.
There is a need to let it dynamically allocate the rack network according to the environment config.