In accounting terms the sale of the Heathrow slots (which if I recall correctly they got about £15m for) would not normally appear in the trading figures, and thus does not count towards the profit of the company now being reported (sorry for doing the boring accounting bit).
The press release doesn't make it clear where this money is accounted for though, or indeed if it even came in during the financial year now being reported on. It does of course contribute to the cash, which probably got used to pay off the debts from past losses. Do I also recall correctly that Flybe had a big loan from the Walker Family Trust ?