I saw some posts stating that you have a better idea of where your at at 65 games. You also have a better idea how your players are doing the following season. With that said I think 50 games is better because at least you have the opporunity to fill holes or make your team better if your a contender. If your rebuilding, there's nothing wrong with telling a manager I like your offer but I'd like to wait 3 or 4 weeks to see how it look like my team may do next season. I just think it gives more options to teams if done earlier.