I think Jet2 at Gatwick is very unlikely, as they have set up quite a decent operation at Stansted which works for them and Gatwick offers fierce completion from not only TUI but also all the low-cost carriers. Southampton I think could work well for them with a couple of based aircraft as said above operating key holiday routes (the usual Alicante, Malaga, Palma, Canaries, Greece, Turkey etc) with some scope of growth in the future. TUI operated quite an awful summer programme in terms of punctuality this year with many long delays, so may be able to entice people away from using TUI at Gatwick.