The "new" Flybe maintenance hangars were built with the capacity to take Boeing 737 sized aeroplanes but they would probably struggle with anything larger.
Hangar 9 - which was known locally as the Vampire Hangar due to its inmates during the 60's & 70's - has a "To Let" sign on it. The largest aeroplane I've seen in there though was a Viscount.
The rumour does seem improbable.