As I recall, the original easyjet announcement said they were adding 2 extra based a/c for winter 18/19 making 14 based, and then a further 3 for peak summer 2019 to 17 based a/c.
The new routes introduced in winter will (unless any were winter seasonal) continue into S19, but although there has been speculation what new routes may start this summer, I'm not aware there has been any official announcement.