What is the latest time to set one's roster? Is it 5 minutes before game time?
You may not change the start/bench status of a player once that player's game for that week has started.
So if Vick has a game on Sunday at 8PM, you can change his start/bench status any time before 8PM.
To be safe, make sure that you make the change at least 5 minutes before the game kicks off (our server's clock may differ slightly from yours).
I will add an entry in the Help documentation to cover this topic.