According to the PMI Guide to Business Analysis, a change request is a formal proposal to modify any document, deliverable, or baseline. It is used to request changes to the project scope, schedule, cost, quality, or any other aspect of the project. A change request should include the following information: the reason for the change, the impact of the change, the alternatives considered, the recommendation, and the approval status. A change request should be initiated whenever there is a deviation from the agreed-upon project scope or plan, or when there is a need to accommodate new or modified requirements. A change request should be submitted to the appropriate authority for review and approval, such as the project sponsor, the change control board, or the steering committee. A change request should also be communicated to the relevant stakeholders, such as the project team, the customer, the PMO, or the operations function. A change request should be aligned with the project objectives, the business needs, and the stakeholder expectations. A change request should be evaluated based on the criteria established by the project governance, such as the business value, the feasibility, the risk, the urgency, and the alignment with the project charter. A change request should be implemented only after it has been approved and authorized by the appropriate authority. A change request should be monitored and controlled throughout the project life cycle to ensure that the expected benefits and outcomes are achieved.

In this situation, the project manager should initiate a change request to modify the scope and adjust the timelines, because there are scope changes and a delay in the delivery of critical tasks that affect the project performance and the stakeholder satisfaction. The project manager should document the rationale and the impact of the change request, and submit it to the appropriate authority for approval. The project manager should also communicate the change request to the relevant stakeholders, and update the project plan and the project baselines accordingly. This way, the project manager can ensure that the project is aligned with the business needs and the stakeholder expectations, and that the project delivers the expected value and benefits. References:

The PMI Guide to Business Analysis, Chapter 6: Traceability and Monitoring, Section 6.4: Manage Changes to Requirements

Business Analysis for Practitioners: A Practice Guide, Chapter 7: Traceability and Monitoring, Section 7.4: Manage Changes to Requirements