Since you are already a senior part way into the year are you still eligible? I would think you'd need to be a junior now and go next year.

If you have an opportunity to do it with expenses covered as a college student I'd do that now. If you were a high school junior and could go for the whole senior year, I'd do that while I had the chance; but that might mean you wouldn't graduate with your high school class.

I suspect that CBYX might be too late for you. I can't see them taking you to repeat a school year when they can offer it to someone else starting their senior year.