I know that every 20 or so cycles (some say 10) you should discharge the battery to 8 percent. I read in one of these threads that you could just remove the props and leave the Phantom on overnight. The user's manual states "Users should discharge the battery until there is less than 8% power left or until the battery can no longer be turned on". If you do that will it auto shut-off at 8 percent? I understand that completely discharging the battery can kill it.