I was guessing something like that, It was a warning to me, if it really tried to land was a free fall from 400 meters....It's because of the VPS.
It thinks you are close to the ground, as the cloud is obscuring it's view.
Good point. Anyhow, If the pilot do not disable the sensor It could reach a state of depleting the battery because the drone will hover or slow descend !?I doubt the wizardry inside will allow the motors to stop because of a 'landing phase', even if it is imaginary, whilst it senses motion.
Now that is a good point and needs investigation!or slowly descend