This is the world’s oldest solution for things that cannot be done. If your team is already working hard at the project, and three weeks early would overwork everybody, say “no.” Many people have a hard time saying this little word, and this is how we wind up with more on our plates than we can handle. Practice saying it, one sound at a time. This way, when that client calls you up and says, “We need this before you’re scheduled to have it done,” you will have a response ready.