Basil, thanks for the link to the August traffic report in the M.E.N.
Near the end of that article there is a link to another Ryanair story which originally included an alleged quote indicating many of the airline's new planes on order would be based at MAN over the next 5 years. I nearly choked in disbelief and I see that paragraph has now been deleted. The 300,000 extra pax a year mentioned appears to relate to the new Eindhoven and Shannon services.
It sounds a lot, but a based 738 with 189 seats doing. say. a fairly modest 18 rotations a week with a few longer sectors for 50 weeks provides 340,000 seats. On the other hand, a 763 daily service to the States has less than half that, but both are extremely important.