Also, you may have more luck with replies if you post this in the P3S forum. There are more P3S owners there in that forum than here in the Pro/Adv forum.
I happen to stumble upon this thread. I am having new P3S bought a week back and having the same issue on my first flight. In middle of a open field beside highways where apparently nothing is there I am seeing this warning message that my long distance flight may get affected.