Every twelve-week build we run is structured around a Friday demo. The demo is the forcing function: anything shippable by Friday lands; anything that isn't gets re-scoped Monday morning. After eight years of this cadence, the engineering team can plan a sprint to a Friday demo in their sleep.
The template: week 1 is discovery review + ticket-grooming. Weeks 2–10 are five 2-week sprints, demo'd on Friday of each sprint's first and last week (so the client sees progress every 5 working days). Week 11 is UAT + bug-triage. Week 12 is launch + handoff.
We write the status note Sunday evening so it's in the client's inbox Monday morning. The note is exactly four sections: shipped, in-flight, blocked-on-you, next.