CCR, "likely" or did you mean "unlikely"? I have no doubt RYR have no intention in creating a base at Derry. Just look at the schedule history.
This fact convinces me that any airline that wants to operate "regional" services from LDY will have no direct competition from RYR. Certainly any MAN route will have to compete with RYR LPL, but that's about it.
If as Gate22 says (and I'm touched by his concern) RYR want to "smoke out" Irish aviation, so be it. Let's see RYR fill a 737-800 to EDI; or MAN, an airport they kicked in the teeth some time ago.