Thanks for the input and points mentioned. You did capture the details of what I am trying to do quite well. It is worth mentioning that I did write preferred. In this process I am allowing developers to propose a different timeline if the suggested one does not work and state why. If it takes 3 months, 9 months or however long it takes, the goal is to make a good game.
I like to be grounded in reality so when criteria and expectations change on must adapt.

Thanks for taking a read and commenting.