How to build a launch timeline

Working days, not calendar days, and the dependencies that decide what can actually run in parallel.

Launch plans slip because they are drawn in calendar weeks and ignore what must wait for what.

Step-by-step

1. List the tasks and how long each takes in working days.
2. Mark what depends on what.
3. Set a start or a target date.
4. Read the dated schedule.

Working days change everything

Twenty working days is a month of calendar time, and more across a holiday period. Plans drawn in calendar weeks are systematically optimistic, and the error compounds across a sequence of tasks.

Dependencies decide the length

Tasks that can run in parallel cost the longest of them; tasks that must run in sequence cost their sum. The chain of dependent tasks is the critical path, and only shortening something on it shortens the launch.

Speeding up a task with slack achieves nothing at all, which is where a great deal of pre-launch effort goes.

The waits people forget

• Approvals and licences, which run on someone else's schedule.
• Lead times for anything manufactured or printed.
• Legal review.
• Bank accounts and payment processing, routinely slower than expected.
• Anything needing another company to act.

These are pure waiting, they are frequently on the critical path, and no amount of working harder shortens them. Start them first.

Add buffer where it protects the date

Padding every task hides the real schedule and gets absorbed anyway. A single buffer before the launch date is more honest and more useful, because you can see how much of it you have spent.

Frequently asked questions

Why do launch plans slip?

Usually calendar days used instead of working days, and dependencies that were not mapped, so tasks assumed to run in parallel actually had to run in sequence.

What is the critical path?

The longest chain of dependent tasks. It sets the minimum duration, and only shortening something on it shortens the launch.

How much buffer should I add?

A single buffer before the launch date rather than padding every task. Padding hides the real schedule and gets consumed without anyone noticing.