DIAMOND AIRCRAFT UK LIMITED
AGRONOMY HOUSE
GAMSTON AIRFIELD GAMSTON
RETFORD
NOTTINGHAMSHIRE
DN22 0QL
Filed their last set of accounts at Companies House in March 08 and are still showing as "active" status, so unless something has happened between March and today, my guess would be yes, they are.
Why not give them a call and ask :
+44 (0) 1777 839200
Diamond Aircraft UK