According to the Scotsman newspaper:
'Hamburg-Edinburgh flights launched
BRITISH Airways is to reconnect Edinburgh with Hamburg, five months after the route was abandoned by German no-frills airline Hapag-Lloyd Express.
BA Connect - the new name for the airline's UK subsidiary CitiExpress - announced yesterday it will operate three flights a week from 2 June.
Germany is Scotland's largest European tourism market and Hamburg is Germany's second biggest city.'
Looks like it only operates on Wed, Fri and Sun though.