So weather put on hold my plans to fly to the summit. It was raining up top and closed to the public.
So I had to drew a quick mission with no cell service. I entered 80 meters above home point. As you can see from video mission started just fine but somewhere in a middle I noticed that drone is on a same level as our car and maybe even lower.
So I decided to pause the mission and safely returned it home.
https://sparkpilots.com/media/whiteface.31/
A very good thing that you stopped.
When planning a mission on the fly with a mobile device only (not including laptops using the web based Mission Hub) you do not have the "Above Ground" checkbox.
You stand a better chance of running into the side of the mountain.
Just as you saw the altitude getting lower.
An "Above Ground" setting would have kept the AC at that altitude from the ground so long as there was a waypoint between the two or more points.