I'm not involved in Jet2 recruitment, and only a minion, but the DFO told us in December that they would be using agencies for some of the crewing needs, as was done a few years ago. In addition we are also recruiting for permanent and contract positions directly.
One additional 757 is coming and 2 737s. However, obtaining the second 737 was proving difficult, so maybe the actual fleet numbers are in question, but I'm just guessing.