That's because they're trying to show investors, and everyone else that upcoming flights are being booked. Which means they have revenue coming in, right? They're not going to admit publicly that they're sunk until it's actually happening... until they are cancelling flights and selling stuff off.
If I had to book right now, I would be going nowhere near AC. Yes, it's a Canadian company and I would like to support them, but I can't afford to support them to the extent that I'm taking a chance on being out a couple thousand dollars.