Apparently, a strike at Boeing means that aircraft are not available:-
BBC NEWS | Scotland | Edinburgh, East and Fife | Ryanair cancels Edinburgh flights
Low-cost airline Ryanair has been forced to cancel flights from its new Edinburgh base for the next six weeks because of strike action at Boeing.
Ryanair said the strike meant US aircraft manufacturers Boeing was unable to deliver two 737 planes it purchased to operate on the new routes.
Ryanair said it now hoped to start flying from Edinburgh on 5 November.