Bob,
your figures make perfect sense, I don't dispute them, but I'm sure many things will change before all the aircraft do arrive. This only then puts FZ in a similar position to most other airlines. I suppose its how you look at the job you have or are considering applying for. If you are joining FZ to get that quick upgrade, then yes, you have to consider the maths just the same as you would when you join any other airline. Fast upgrades can't be sustained forever.
Maybe I was wrong, but I considered the earlier comments to be an implication that FO's already at FZ were virtually already in dead mens shoes. Something I could't disagree with more.
SW