As I read it, after 10 years they can apply to stop using it for aviation purposes, but that doesn't mean they can then do what they like.
I'd love to see Carlisle have an aviation future but it just isn't commercially viable and never will be.
Come the moment, Stobart will merely point out to the Local authority that their plans to develop the site as a major transport base will bring far greater long term local employment and a vastly greater economic contribution to the region than the airport ever would and their plans will sail through.
Not only that, they'll be perfectly justified.