A moved launch date changes the order and ownership of work, not just the calendar entry. First confirm the new release time and any fixed dependencies: approvals, external announcements, support coverage, and deployment windows. Recalculate the latest safe time for each prerequisite. Then mark items as complete, still required, or no longer relevant; do not silently skip a security or rollback check to fit the new date.
Send the revised checklist to each owner with a due time and a clear go/no-go decision point. Run a small rehearsal of the critical path if the change introduces new handoffs. Record why the schedule moved and which evidence must be present before launch.
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