I am creating a mission into a valley in the mountains using DJI Pilot.  I have a Matrice 210 V2.  The valley is very deep and I will be launching the mission from atop the mountain ridge.  During the mission I need to drop to -215 meters below the ATL elevation in order to go into the valley.  However, the DJI Pilot app only allows a minimum of -120 meters and when I try to set anything below that, it defaults back to the minimum of -120m.

How do I fly a mission into a valley if I cannot get lower than -120m below ATL?

I ask this in order to maintain the US maximum flight height of 400 feet above ground (AGL) for FAA regulations.  Also, anything above 400 feet and my video/photo capabilities are limited and useless, therefore, being able to set the height (ATL) to below -120 minimum is a must.

Please help.  Thanks.

Yeah this is a frustrating limitation. I'm having similar issues planning mapping flights within pilot and adding custom cameras etc.

Edit: You may have to fly this one manually? Or find a 3rd party app that can help