How does Solo know it's altitude. Is it based on it's current location or from where it took off? This might be a really dumb question, but I am new to this and can't seem to find the answer. I live in an area with many hills and close to some mountains. I do not want to try follow me and have Solo run into the ground as I drive up a hill. I've tried flying it over a three foot berm and it did not adjust as it went over it. If I hovered over the high point it did adjust but took 5 to 10 seconds to do so. So I am guessing it reads the ground somehow.