In an iterative project, when a new compliance requirement is introduced that impacts the project, it is essential to update the project documentation to reflect this change. The product backlog is a living document that captures all the requirements, including new and changed ones, that need to be addressed in the project.
By updating the product backlog, the project manager ensures that the team is aware of the new compliance requirement and can plan for its implementation in upcoming iterations. This action aligns with the agile principle of welcoming changing requirements, even late in development, as a means to enhance customer competitive advantage (as per the Agile Manifesto).
: = The answer is based on the best practices outlined in the PMBOK Guide and the Agile Practice Guide, which are part of the PMP certification materials. These guides emphasize the importance of maintaining an up-to-date product backlog and incorporating changes that may arise during the project lifecycle.

The project team is in the "Storming" phase of the Tuckman Ladder Model. This phase is characterized by conflict and disagreement, where team members challenge each other, the project, and its leadership. The discomfort among team members and the challenges to the schedule are indicative of this phase. It's a crucial stage where the team starts to address the project's tasks, plans, and ideas, leading to various opinions that can cause conflict. The project manager's role during this phase is to help the team resolve conflicts and disagreements and guide them towards a common understanding and cooperation12.
References:
What is the Tuckman Ladder Model? Learn 5 Stages of Team Development
What is the Tuckman Ladder Model? 5 Stages of Team Development.

When a product owner requests the addition of a new mandatory feature during a sprint, it can disrupt the planned work and cause frustration within the team. The best course of action is to engage the product owner in prioritizing the product backlog with the project team. This collaborative approach ensures that the team understands the value and urgency of the new feature, aligns on the priorities, and adjusts their work plan accordingly. It also helps in managing the team's workload and expectations, preventing overcommitment and potential burnout. By prioritizing the backlog together, the team can make informed decisions about what work to focus on during the sprint, ensuring that the most critical features are delivered first.
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