Ah yes they did, RYR Ostend but to London (Stansted)only. Surely, it's the London pax that don't need a short hop over the channel. Add another 200-400 miles road journey (ie MAN, NCL,GLA) then an Ostend service would become more viable. Short hops can also be viable to dovetail into a schedule to maximise useage of the fleet & crews.