Tank aces campaign turn length?

With the tank aces campaign coming up I need to nail down the specifics of how we are going to run this. This is your game and the length of each turn should be decided by the players and not just me. The campaign will consist of 3 turns each of which can last as long as we want them too. I think the best options are either one or two weeks per turn. One week will allow the entire campaign to be wrapped up in a month including a large mass battle at the end while two weeks per turn will extend the whole thing to about 7 weeks (also including a mass battle at the end) but will allow more games to be played each turn which will help to ensure everyone has a chance to get multiple games in each turn which is a key point of the system, the more games played total each turn allows for more uncertainty as to the final outcome of the campaign as well as more chances for everyone to build up their tank ace. Remember the more games you play the more experience your own ace will accumulate and thus the more unique skills he can obtain.

so how long do you think a turn should last?