This also occurs in the new 7.5.19. I agree with Dennis, it maintains the original airport and not the new one you view when you select nearby. Oops! That can create a lot of confusion..
This doesn't happen when you go to "Menu" "Find Nearest" then select. but if you then say "Nearby Airports" once again, it will not refresh the airport view with the new one. It re-displays the original one...
Wade