Reading about many flyways and having some personal very close calls on the topic I have come to the conclusion that many pilots rely far to much on the Phantoms GPS features and don´t understand that satellites come and go. >6 satellites is NOT at all granted 24/7! One moment you can have 10, the next 4 and you are in severe trouble! PLEASE ALWAYS CHECK SITES LIKE: http://www.swpc.noaa.gov/SWN/index.html and http://satpredictor.navcomtech.com before take off. There are good apps also like GPS Plan. When you get <6 satellites a lot of things will not work like you are used to, RTH, Home Lock and Course Lock for example. If the Phantom goes in and out of satellite coverage strange things can and will happen! New Home Point set, Auto landing etc etc, Taking off with <7 satellites is a calculated risk taking! If you do this in a satellite shadowed area and expect >7 satellites higher up LET HER SETTLE ON THE HIGHER ALTITUDE TO SET HOME POINT! Just in case better flip S2 5 times up and down and watch green blinking indicating you have a Home point! Don´t think getting >6 satellite "on the fly" will do you any good! If you experience any kind of satellite glitch during flight. TAKE HER HOME IN ATTI MODE RIGHT AWAY! This is almost impossible without FPV if she is far away. Even in LOS it can be very difficult to see what direktion she is in in order to steer her. If you use sites/apps that predict satellite coverage and learn to fly in ATTI mode with FPV you will be much safer!