I have an emergency that requires that I leave early for a business trip. I was originally taking Allegiant to and from Vegas, but now I have to take another airline out. My original flight was not refundable, which I'm okay with. I've heard of situations before that airlines might cancel the return flight if you miss the departure. Is this something I should be concerned about. I emailed alliegent, but it says it can take up to 48 hours to get a response.