If you can't change deadline as you learn, you have to control scope with an iron fist from the outset. I've worked on projects where deadlines were revised ea

If you can't change deadline as you learn, you have to control scope with an iron fist from the outset. I've worked on projects where deadlines were revised each month based on new info, and effort/improvement was focused in gathering better info to inform an (ideally) increasingly accurate deadline confidence. For fixed deadlines; scope, scope, scope. Cut the scope and take an honest look at why it is late ... start fixing those things with a smaller scope. I'd never as a team to work overtime, and I work hard to ensure that situation never risks my teams jobs. If it comes to a crunch, the business failed their staff terribly.