Still hear the rumour every few months that TUI will close their Luton hangar. I always remember working in their concrete ops centre which was a major operation by the old control tower. They had several other offices and buildings around the airport and of course their old hangar that ended up as easyJet’s HQ.
TUI have a large office block around a mile away but I think that is more holiday rather than airline focussed. I think ops ended up in Germany.