Something I don't understand

I found this tutorial on elevation. More specifically, on how to identify the exact elevation for your specific approach when playing it for the first time. Here it is: https://youtu.be/Y8U_kW3pYQs?si=49qT61snrmRvkNv0 Now, on most of the shots, I find it extremely helpful. What I don't understand, though, is how exactly to apply the same method to uphill shots.