Edge Computer - Change Altitude of Copter in Auto Mode

We are using an edge computer providing instructions to ardupilot on a pixhawk 4 flight controller. We want to send a MAVLINK instruction to change the altitude while in auto mode on way to a waypoint without loiter. The command MAV_CMD_NAV_CONTINUE_AND_CHANGE_ALT seems to be unsupported by ardupilot. What mavlink command(s) should we use?

If we use MAV_CMD_DO_CHANGE_ALTITUDE, what followup instruction is needed to go to new altitude?

You should first test it in guided mode.

I don’t think yo can change altitude during a mission. I think it is only supported by plane firmware, not copter. It is a shame i would love to have it on copter too.

But with what command to change altitude? These commands from the documentation does not seem to be part of the guided mode instruction set:

Since the above do not appear as acceptable instructions for the copter (ardupilot) does it then mean we should use a companion computer to dynamically create and insert a waypoint to alter the altitude?

So from what I can gather, we will have to use the SET_POSITION_TARGET_GLOBAL_INT command with appropriate type mask. Is this the only way, or is there another?