I have the same requirement. One spot I fly at has a large mountain less than a mile away, but I can't reach the top of the mountain- I can only fly up to the mountain side. At no time am I more than 200 feet above ground level, but I reach 1638 feet when closing in on the mountain. I'm pretty sure it's a no-brainer to actually reach 3100 feet above launch point, but alas we will never be allowed to do that.
I'm curious what is the baro reference altitude for the MP? The takeoff position? What if you fly up to the mountain (~1600ft) and land somewhere then takeoff again? Does it mean a new ref altitude or it is measured upon power up?