Be aware that in order for your temporary JAA validation to be valid for more than a year, you will need to do all 14 JAA theoretical exams.
That's the JAA requirement anyway. Given the craven, spineless donkeys that work in the IAA though, who subvert the law to their own ends, who knows what the requirement would be in a years time.
While not au fait with cityjet management, the grapevine has it that they're from the ryanair school of truth, i.e. will tell you what you want to hear, but in fact are connsumate liars who will do what they please without regard to promises/contracts etc.
Expect supply and demand be the deciding factor. If you're surplus to requirements, expect a knife in the back.