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Keep a dated approval trail for each client deliverable proof.
Keep a clear history of who approved or rejected each campaign proof, even when the review board status changes later.
Hold client handoffs until revised proposals have a fresh review.
Your delivery manager sees changed proposal terms and a pending review before the team moves forward.
Prepare client project folders for delivery handoffs.
Your project handoff task points to a folder with the right Agile or PRINCE2 phases, while your lead sees what details still need attention.