The same thing happened to us when we bought a 20' The dealer installed another hook between the windows and had the strap on the awning moved. So now we have two hooks and two windows that open all the way. The dealer and we called Airstream. Airstream paid for all the modification work. We did not let them move the original hook for fear of creating leaks so we have two hooks.
Richard from MI
20' 2008 Safari SE, Dill TPMS Silver Dog House
2007 GMC 1/2 ton Sierra ARE Cap
AIR # 10494