I say Go for the regional now. At my airline I seen a few guys lately heavier than 290 in the right seat. As someone mentioned above the regionals NEED pilots, you'll be surprised how fast they will reply to you and how easy the interview are these days. If you need any suggestions on a Regional feel free to ask.
My coach once told me I need to get back into shape, I said hey Round's a shape. Lame I know. good luck mane!

oh yeah.. hydrate, stay away from the bottle and get at least ONE cardio session in daily. you need to loose mass in the short term, not gain muscle. Once you get to a weight that's comfortable then you can start adding muscle strength into the mix. just my thoughts. you got this.