I am not aware of any way to change just the fabric, which it sounds like what you want to do. This would be like trying to change the vinyl in a spring-loaded roll up window blind, only worse.
I helped my brother install an entire awning on his Titanium and that is a doable 2 person job, with 2 good step ladders. CW charges $61 to install this awning
and I would not do it myself for that money if one is close by--check a local RV dealer first--shipping won't be cheap either.
The awning is attached through a small channel under the gutter. A small piece of awning fabric is wrapped around a steel rod and the whole thing slides in or out from the front end--the 2499 has a gutter extension on the back that would make it hard to slide in that direction. There are also two small screws that hold the awning in place in its channel--you can see these by looking up the side of trailer.
I can't remember all the details of the install. My brother, the engineer, looked after that--I was just the the guy on the other end.
It might help if you tell us why you want to change the awning--dirty? torn? etc.? Someone might have an alternate much cheaper suggestion or fix.
I just saw this link on galaxiedriver's post so there might be a way to change just the fabric.