DJI’s GSP product may not support M3… they haven’t expanded GSP much… Last update over 8 months ago.
Although when SDK is released, you’ll see most 3rd Party add the M3 to their product. That will most likely include MapsMadeEasy, Flight Plan, Litchi, DroneLink, UsGS, etc.
Mapping should be available in near future.
If Craft FW will support Waypoints and Autonomous missions is an unknown... If not, like all the Fly App crafts (Air2, Mini2,etc) will require a connection to Radio & App to send mission data to craft. Your M2P can continue to fly mission if radio connection is interrupted or lost… like all crafts on the Go4App.