I appreciate why you want to move back to BFS and Jet2 sounds like a nice little number too.
However, few points worth thinking about!
Jet2 is a bucket and spade company. Most holiday companies don’t do too well during down turns and anyone who thinks otherwise is in denial. I remember people at Jet2 were put on to 75% contracts and worse during the last recession. I would also say the outlying bases at Jet2 would be more ripe for the cull in such a scenario. Something worth thinking about.
If you are desperate to get back to BFS, why not look at EZY? Much more established at BFS and a much more secure company. It might cost you more to go to EZY, but I think it would pay off in the long run.