Interestingly it is reported they will have 36 routes in Summer 2015 (compared to 38 this summer), which I make including the new Malta route means three routes are being axed. I expect Cork to be one of them.
So dependent upon which routes may be closed, and the number of weekly flights that they are increasing by on those routes they should be able to achieve this without increasing capacity.
I'm always very sceptical about Ryanair claims of "new" services and "extra flights" as there is occasionally some
PR license used - e.g. the extra flight to Alicante might be just in July and August.
The devil is very much in the detail - and what is published today, may not be the reality in 12 months time.