@Carl Thanks for the pointer. My visitor has left, but I'll try that the next time and see if that re-routes them. Also, I'll have them do a speed test before / after optimization.

I have deco M9 on 1st floor, Main on second floor, 3rd on 3rd floor. All the Apple devices - iphone, Mac and iPad sitting in the first floor bedroom - all show connected to the 3rd floor M9 Deco!!...