I think the fall back business plan is that .....they don't have a fall back business plan. They have sought the Holy Grail of significant passenger operations and let everything else slip. With the right investment they could by now be the West Midlands Bizjet centre (look at what Oxford are doing for example), they could have developed GA (look what Kemble are doing for example). The only slightly bright thing is that despite the airports lack of interest and Parcelforce's treachery, the freight has held up reasonably well.
Going back to Howard Holdings, whatever happens they are going to take a huge hit. They reported paid 30m Euros for the place from TUI. They ain't going to get that back if they sell and they are going to have to invest to get it back long term if they stay.