FR,
To get back on thread. Why would Jet2 want baby?
Realistically, I can only see Jet2 wanting it for the routes and airport access; while their classics may be older than baby's, I believe they do have some NGs on the way.
Within the Eu Open Skies area, a route is just a line on the map - at the destination end, where if anywhere would baby have a better deal than Jet2? As for the UK bases, Jet2 have seen baby off at MAN, baby have retreated at MME, perhaps the reasonable sized northern airport Jet2 have shown no interest in, and so far, the space left vacant at CWL is still largely vacant.
EMA is much less busy then it used to be - if Jet2 want to expand there, who is going to stop them, with or without baby. As for Belfast, no way Jet2 would want two bases in a relatively small market.
So that leaves BHX, and airport with big ambitions for long haul, but huge gaps in its short haul network. Again, if Jet2 wanted in as is, they would presumably be welcomed in with open arms. Flybe already enjoying no competiton on the Scottish Central routes, Ryanair could fill many of the gaps left if baby went, especially now they aren't so picky about using the cheapest airports.
Baby going might leave a space for Easy to take another look, but I just can't see why either airline, or any of the others would need to take on the fleet / staff / contracts of baby when they could just cherry pick the routes which will suit their busines model, instead of adapting to fit the deals negotiated by the incumbent carrier.