Jet2 won't change type any time soon. They have got a fleet of mainly owned aircraft, which in their older age will not be so easy to shift. With type change comes expense. 737-9's are more likely as they have been going a few years now and are on the second hand market already. I would also certainly not rule out the 737MAX's, but of course, these are brand new, and if ordered, would be of a fewer quantity (maybe 5 or 6). One thing for sure, they won't be changing type to Airbus, even if they do have one on lease for the summer.
