When a customer requirement change is identified, the project manager should first validate the change with the product owner and the development team. This ensures that the change is feasible and assesses its impact on the project. The PMBOK Guide outlines the importance of involving stakeholders in decision-making processes and the need for integrated change control to manage changes effectively.
References: The response is based on general project management principles as outlined in the PMBOK Guide and the standard practices of stakeholder engagement and integrated change control that are part of the PMP's body of knowledge

In an agile project, it is crucial to continuously assess the project's direction and priorities to ensure alignment with business objectives and adapt to changes in the business environment. Reprioritizing the backlog after every iteration allows the project manager and the team to evaluate the value and relevance of user stories in light of any new developments or changes. This practice ensures that the project remains focused on delivering the most valuable features to the business and can adapt to changes quickly and efficiently.
References: (Professional in Business Analysis Reference Materials source and documents)
* A Guide to the Project Management Body of Knowledge (PMBOKGuide)
* The PMI Guide to Business Analysis
* Business Analysis for Practitioners: A Practice Guide