As far as new aircraft coming to jet2, I think they will replace the Icelandic aircraft ** with there own in the next 12 months and the 757's would then be the only increase to the fleet size. But you never know what might happen with a company exspanding as quick as Jet2.
**(could be the Icelandic intrest, as the company we have leased aircraft off the company for a while now, and was taken over by Air Adlanta not to long ago. Not to sure of any conections to the east side of europe? )