Let’s be realistic, all they’re going to do is dump capacity on bucket and spade routes in an attempt to trash yields for the competition. If it’s based aircraft it’s going to be Malaga, Faro, Palma, a couple of Greek islands, Milan and the Canaries.
Which is a shame because there are plenty of gaping holes in the route map south of the river, such as Warsaw and most of the Balkans, that would be most useful for Gatwick.