Yup, more naming confusion from DJI... "Autopilot System" on that page is referring to the Vision's Naza flight controller. "Main Controller" in the Assistant app is referring to the Vision's Naza flight controller, too... wish they were consistent across manuals, software and website - it would stop people plugging in the "remote controller" (which they should call transmitter to avoid confusion) when they saw the message in the Assistant instead of plugging in the aircraft.