It says this on the pinch-hit post, but—in the claim post, only people signed up as betas can work as betas. On the pinch-hit post, anyone affiliated with the big bang can fill any position, if they have time for it. Writers can work as artists! Artists can work as betas! Betas can work as artists! It's like saturnalia, except without all the chaos. So you stand a better chance of finding a beta, and it's at least worth a try, yes?