This from a facebook post, can't verify authenticity but it might help.
"For anyone in the UK that booked through Tui, and booked in a store, the online staff cannot access your details as it's a different system. however, a friend of mine who works in store for Tui has told me that from this Wednesday, 200 staff will start contacting customers to rebook etc. More staff will be available once they receive laptops that are set up for them to work from home. They will be doing it in order of peoples travel so be patient."
aka TUI customer service cannot just pick up their office systems and work from home. I'm sure the IT guys at Wigmore Place in Luton will be busy putting in infrastructure for the direct bookings employees as well.Hope that helps.