As noted here:
"Maximum Flight Height - DJI limits the height an aircraft can fly to 500 meters with respect to the takeoff point. A warning message and a red line will appear in the elevation plot to show the areas that are over the 500 meter limit. When a red line is present you will not be able to accept the terrain adjusted flight and take off."
You can only fly 500m higher than the takeoff point. You can also not fly more than 200m below the takeoff point. So... You can start somewhere in the middle and do it all at once or you will have to break it up.