Slot delays in peak summer are a fact of life for all operators. My gut feeling is that manning levels are under severe strain right now at jet2. To take a 4-5 hr delay at a main base with an operator that supposedly keeps 4 aircraft + crew on airport standby indicates a severe shortage of some sort?
I have no dog in the race, other than alot of ex colleagues who earn a living there. I only hope that management there grasp the severity of the problem in time.