the notion that flybe2 will simply serve the off peak leisure market is unlikely, it it more likely that one operator will leave the market.
....and that's why I said "initially" as ultimately you'd imagine that Flybe would like to become the dominant operator. Sensible to start small, try to build a niche and use that as a basis for expansion.
No doubt that will happen if they can provide a decent service at a decent price (in a way that works from a business perspective also!)