All my sceneries (add-ons or even the ones offered by Asobo) have this issue. I think a picture is better to describe the problem (here in Geneva for instance).
I think I found a workaround here, I went to settings and disabled bing live map and photogrammétry. Apply settings. Then I put it back again. Now everything is back to normal
The first seconds the new reloaded texture will be blurry but then it will be back to best quality.
I found out the issue occurs when there is an aerial CGL placed on or near the airport area. It doesn’t happen without the CGL and it never happened prior to SU9beta