During the Team Breakout portion of PI Planning, the hourly activity that helps keep teams on track and facilitates early identification of risks is the ART planning board inspection. This activity involves reviewing the Agile Release Train (ART) planning board, which provides a visual representation of the team's plans and progress. It allows for the identification of dependencies and risks, and ensures that all teams are aligned with the ART's objectives. The planning board is a central tool in SAFe for maintaining synchronization among teams and providing transparency into the work being done. It is not the Iteration Review (A), which is a separate event that occurs at the end of an iteration. Coach Sync and Business Owner feedback meeting (D) are also important activities, but they do not specifically serve the purpose of an hourly check-in during the Team Breakout sessions to keep teams on track and identify risks early1.