I don't have any sour grapes as I've never worked for Jet2. I did have a serious look at it earlier in the year and decided the whole employment package was way to one sided. All the risk on my side and no risk whatsoever on thier side. (especially having a £5000 bond even if you are type rated)
Bear in mind I do have a job. If I didn't then the whole thing takes on a different perspective.
Have a look at ppjn for employment terms. I don't know how up to date it is but it might further your investigations.
There is also an extensive discussion in this forum entitled "Jet2 an honest and uncensored debate..." or something along those lines that might give you a feeling for what is going on. Be aware that a 757 has a far greater endurance than a 737 and therefore you can expect to have a longer and therefore more unsociable day to day existance than what some might suggest at Jet2.
But at the end of the day, at least you're not having to fly an Airbus!! every cloud and all that.