Final answer:
The Program Backlog should be reviewed continuously, with special emphasis on a more rigorous review before every Program Increment (PI) planning session to align with the ever-evolving business and market conditions.
Step-by-step explanation:
The frequency of reviewing the Program Backlog should be continuously. The Agile framework emphasizes the importance of maintaining a dynamic approach to product management. The backlog is a prioritized list of features, user stories, and changes that serve as inputs for Program Increment (PI) planning sessions. Continuous review allows for the adjustment of priorities based on new insights, stakeholder feedback, and changes in business objectives or market conditions. While active review may happen throughout the PI, it is particularly important to rigorize this process before every PI planning event to ensure that teams are prepared to discuss the most current and relevant items.