My GF's Crusader 5th wheel awning is also "shedding" the top layer up at the top where it attaches to the awning rail. That part of the fabric is always exposed to the elements and especially sun damage. Using "alumigard" coverings will help but a likely expensive option if added later. Anyway my plan is to replace the fabric next year and I wanted to extend it's life if possible. I got appropriate Gorilla tape and made patches where the layer was separating. The tape patch will probably last as long as the fabric. If not, nothing lost except a little time and tape. My 2007 Itasca motorhome had the awnings, main, door, and 2 window awnings with the alumigard section. Original awnings were in great shape. A little precaution goes a long way.
2020 Raptor 356
2012 Crusader 355BHQ (girl friends)
2017 Ram 3500 Laramie 4WD, SRW, CC, LB, 6.7l
2019 Harley Davidson Heritage Classic 114 (the toy)