That Aer Arann service has been scrapped. I can only assume this is because it worked out too lengthy with a connection to justify people paying for it.
I've just always thought that some kind of service direct between LDY and ORK that say only ran around the weekend could have been easily marketed in both cities.
The fact that these days the quickest and easiest way of getting from Derry to Cork is still just driving yourself is a bit mad. Pity.