The Team Planning Workshop is primarily held to update the product backlog. This collaborative session allows the delivery team to break down, refine, and reprioritize user stories or tasks to prepare for the upcoming iteration or sprint. The team reviews the product backlog items, clarifies acceptance criteria, estimates effort, and commits to the planned work.
Updating the product backlog at this level ensures that detailed planning aligns with the overall project vision and release goals. It empowers the team to self-organize and manage their workload, supporting agile principles of autonomy and collaboration.
While the project dashboard (A) provides status reporting, the release map (C) focuses on higher-level release planning, and OKRs (D) relate to strategic objectives, these are not the central focus of the team planning workshop.
PRINCE2 Agile promotes team planning workshops as essential forums for translating business priorities into actionable, manageable work for delivery teams.
Reference: PRINCE2 Agile Foundation Version 2, Section 6.3 "Team Planning," and PRINCE2 Agile Study Guide, Chapter 6.

Reference https://publications.axelos.com/prince2agile2016/content.aspx?
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