There's still some amount of uncertainty over Aer Lingus's plans for next summer. There are rumours of two 737s that are being leased. Also the Shannon timetable currently suggests an aircraft based in Malaga for the summer period (probably only possible with a wet lease). Seeing that there can be up to seven flights a day to Malaga from Dublin, Cork, Shannon and Belfast, it could make sense and allow freeing up of aircraft across bases rather than putting all the extra capacity in one location.
It still is a case of Watch this Space.