I go to Joanns but I scrutinize the fabric closely before I buy it. I have only returned fabric once - and I didn't even know that you could until I witnessed a customer return some. (I returned some of their black country classic fabric as I started buying Kona - and there's no comparison.) You can return if you haven't cut into it yet.
I have no expectations of their being able to answer any technical questions I might have. I have stopped buying yards and yards of clearance fabrics because I can't tell for sure, but, it looks like I'm being overcharged, I usually buy only with coupons as I'm one of the millions who are unemployed. You can use the same value coupon for different things if they are from different media ... the mailer, the Sunday paper, email, etc.
I am currently in the "middle" of trying to get something ironed out regarding the coupons with Joanns, but, they seem to have abandoned me. I will move to snail mail and see if I might have better luck and will post what I find out. Unfortunately I don't think I will be able to locate my original post - guess I've been unemployed too long and my brain is beginning to rust.