Nope, because the Typhoon actually needs three waypoints (the 'current' one that it's just reached, plus the next two) to be able to calculate the curved cable cam route. For those who've worked with CAD software, it calculates a spline through the three waypoints. If it just sent a waypoint at a time, we'd see kinks and jumps as it went from one section to the next.
So it's definitely not sending a single waypoint at a time, and it doesn't make any sense to send just three when you could send the whole mission. Remember also that the Typhoon is flying at 11m/s for a mission. If the signal is delayed when it's going from one waypoint to the next, the Typhoon would be flying 'blind' until the next instruction was successfully sent.
You can check out the PX4 architecture (
Architectural Overview · PX4 Developer Guide) for an idea of how it all hangs together for an equivalent flight controller, but in essence there is a 'Flight mode' (e.g. Flying manually, flying a mission, return to home) that decides what it is doing. That flight mode runs a given loop/program unless or until it's told to do something else. That 'instruction to do something else' might be a command from the ST-16, or a signal from the flight controller itself. One example of a signal from the flight controller is loss of R/C connection for more than a certain period. When that happens, the current flight mode is stopped, and the return to home flight mode is triggered.
So the flow is more like:
1. The mission is uploaded to the H. It enters CCC mode, flies to the first waypoint and waits
2. The Typhoon continues with the mission (initially just waiting)
3. If the ST-16 sends a speed command (ie start mission/reverse) the mission is started, slowed down etc.
4. If signal is lost for more than a certain period, RTH is triggered.
5. If the mission is complete, the Typhoon waits at last waypoint
6. Goto 2