A new preview is up in which the development team says the turnover issue is fixed. Too bad, I don't believe them. I can't remember who asked about the number of seasons that can be played, but that is addressed in the preview as well - 60 seasons in the 12 player MP online league. I believe it is the same for single player.
http://www.gametap.com/articles/game...x_360-04292008