When a project experiences schedule delays, especially with tasks on the critical path, it is crucial to review the critical path with stakeholders. This collaborative review helps in understanding the impact of the delays and in defining the next steps to mitigate the issues. The stakeholders, including the project team, suppliers, and sponsor, can provide valuable input and decision-making power to help navigate the issues1.
References:
PMBOK Guide - Sixth Edition2.
"19 Frequently Asked Questions on the Critical Path Method" by Praveen Malik, PMP3.
"Exam PMP topic 1 question 321 discussion - ExamTopics"1.
"Five Tips for Being Prepared for Supply Chain Disruption" - PMI.org4.

Checking the risk register for a prepared response to a resource being suddenly unavailable is a proactive action that the project manager should take to deal with the situation. The risk register is a document that records the identified risks, their causes, impacts, probabilities, and responses. By consulting the risk register, the project manager can see if there is a contingency plan or a fallback plan for the loss of a key resource, and implement it accordingly. Checking if the team member's activities are sufficiently documented to facilitate handover is another important action that the project manager should take to ensure the continuity and quality of the project work. The team member's activities may include tasks, deliverables, dependencies, assumptions, constraints, and other information that are relevant to the project scope, schedule, and cost. By reviewing the documentation, the project manager can identify the gaps, risks, and issues that may arise from the absence of the team member, and take appropriate measures to address them. References: (Professional in Business Analysis Reference Materials source and documents) PMBOK Guide, Seventh Edition, Section 11.4.3, "Risk Register" PMBOK Guide, Seventh Edition, Section 4.3.3, "Project Management Plan" Professional in Business Analysis (PMI-PBA) Guide, Section 4.2.2, "Documentation"

According to the PMBOKGuide, the project manager is responsible for performing integrated change control, which involves reviewing and approving change requests that may affect the project scope, schedule, cost, quality, or other aspects. Therefore, the project manager should review the benefits of the proposed changes in relation to the business case, which is the document that justifies the project initiation and continuation based on the expected value and alignment with the organizational strategy. The project manager should evaluate if the proposed changes are necessary, feasible, and beneficial for the project and the organization, and if they outweigh the potential costs and risks. Assessing the time overrun, and starting implementation to avoid additional delays may not be the best option, as it may result in scope creep, quality issues, or stakeholder dissatisfaction. The project manager should not implement the changes without reviewing and approving them first, and without communicating them to the relevant parties. Requesting a provisional budget increase to avoid any budget overruns may not be possible or timely. The project manager should not request more funds without analyzing the impact of the changes on the project budget, and without obtaining the approval or guidance from the management or the sponsor. Motivating the team to avoid the frustration of working on a prolonged project may be a good practice, but it is not the first thing the project manager should do. The project manager should first address the change requests and their implications for the project, and then manage the team's expectations and morale accordingly. References: PMBOKGuide, Sixth Edition, Chapter 4, Section 4.6 (Perform Integrated Change Control) and Chapter 5, Section 5.1.3.1 (Business Case)

According to the PMBOK Guide, a business case is a document that provides the justification for undertaking a project or an additional scope, based on the estimated costs, benefits, and risks. A project manager should develop a business case and submit it to the client when they realize that some minor changes could deliver significant benefits to the client early. This will help to communicate the value proposition of the changes, and to seek the client's approval and support. Developing a business case and submitting it to the client is the best approach that the project manager should take in this situation. Concentrating on the current project milestones (A) may not be optimal or beneficial, as it may miss the opportunity to enhance the client satisfaction and project outcomes. Updating the project management plan for this new work (B) may not be feasible or ethical, as it may violate the project scope, schedule, and budget baselines, and the agreed-upon project objectives and deliverables. Making all the changes and then showing the client the results (D) may not be appropriate or acceptable, as it may create scope creep, increase project risks, and damage the trust and relationship with the client. References: PMBOK Guide, 6th edition, pages 33, 75, 129.

When a late concern arises after prototype approval and development has started, the project manager should acknowledge the stakeholder, assess the request through the agreed change/priority mechanism, and preserve commitments needed to finish the current delivery. Placing the requirement into the next deliverable cycle (D) is typically the most practical action because it respects the already-approved baseline (or sprint/release commitment) while still addressing stakeholder needs via backlog/release planning. Being firm dismissively (A) damages relationships and fails stakeholder management. Documenting and "engaging more often" (B) is generally good practice, but the immediate next action is deciding how to handle the request within the current project's stage and commitments. Telling the stakeholder nothing can be done (C) undermines collaboration and ignores adaptive planning; even if it cannot be included now, it can be scheduled. Including it in a future cycle supports transparency, maintains delivery focus, and provides a structured path for evaluation (value, effort, impact) and prioritization-core PMP objectives around stakeholder engagement and integrated change control in an agile or hybrid setting.