I understand that, My question in simple term's is would retiring the A-10 as the USAF want's to do make much of a difference, One might only need 10 people to keep it operational while another would need 30. What should also be questioned though is why the rush to retire the A-10 if the F-35 is not actually combat ready and not expected to be until 2020+.
I suspect that is very dependent on what you expect from your maintenance crews, how well trained they are, and what kind of turn around you want. One well trained mechanic might be enough if you didn't mind the plane not being in the air for the rest of the day (or two). On the other hand if you want say 1 hour turn arounds and thorough checks of everything you are going to need a lot more bodies. All most all if not all will need a significant amount of training as well but more training and experiance can shorten times or require fewer bodies. If you do get numbers you need to look at what the turn around times and basic maintenance being performed is as well. There's also the question of how you count it when some activities are moved off the flight lines and back to higher level maintenance. The personel are still required indeed if you count those needed to move the parts in both directions even more may be requred but the training levels will vary.