Help with setting up a Y4+1 configuration

I’m currently trying to implement a drone that makes use of a Y4 +1 configuration ie a normal Y4 configuration + 1 propulsion motor.
I’ve been told that Y6+1 is currently possible but was wondering if anyone had any idea if Y4 +1 has been done before/ if Ardupilot is capable of a Y4+1 configuration at the moment.