That is an increase of 2 flights p/w for knock. Great news for a 2015 that's not looking especially promising. This is not yet bookable from the website, where did you get this Information? Also it may only be the extra 2 flights for the months of June and July.
Ei could not/will not operate a A319 on the noc/bhx route.
1). I doubt they see a market.
2). They do not base aircraft at Knock or Birmingham
3). I really do not see any new short-haul routes for anywhere outside Dublin.
It also looks like Ryanair will start serving the UK routes from shannon from September onwards.