Rome is up to 6 per week for winter, this accounts for 3 of the 4 Prague slots.
Romes been changed back to 3 weekly, but on different days to before. Cork-Rome will now operate on Wednesdays, Fridays and Sundays. This means theres a gap in the schedules on Monday, Tuesday, Thursday and Saturday afternoons as well as Thursday morning. Its highly unlikely that they'd pull the fourth aircraft since there is currently only 5 free slots per week while the A320s operate on average 20 return flights per week so new route(s) seem likely or at least increased frequencies on existing routes.
I still can't understand why EI are axing Cork-Prague. It was meant to operate 4 weekly for the winter. If the route was struggling, why not operate it 2 weekly? From what I heard, loads were very good on the route but perhaps yield wasn't great. They could probably make more money during the summer with a sun route but I don't really see what they could operate during the winter that would be more profitable?