Relax. Apply to other airlines. Relax. Interview at more than one place. Relax. Get hired by more than one. Relax. Choose from the offers that were made and take the best one that fits YOUR particular situation. Did I mention relax?
I think a quick poll on the regional board will turn up several folks who jumped at the first part 121 offer they had and ended up switching between regionals within a year.
Next, remember they are a big company, over 1550 pilots, and although they are hiring many, unless you are the former CP of Cathay Pacific or similar, wait in line. They'll get to you.
Oh, yeah...relax.
HTH
Spongebob