According to project management best practices, a change request is a formal document that describes the proposed changes to a project and the impact they will have on the project scope, schedule, budget, quality, and risks12. A change request should be initiated by the party that is requesting the change, not by the party that is delivering the project3. Therefore, the receiving manager should be responsible for issuing a change request to the project manager, who can then evaluate it and approve or reject it.
Delivering the project to the receiving manager on time, without ensuring that they are ready to accept it, could lead to poor knowledge transfer, lack of ownership, and increased risks of errors or defects4. Informing the project sponsor of the delay and replanning the activities could be done after the change request is approved, but not before. Issuing an internal change request to secure the resources for an additional two weeks could be seen as a unilateral decision by the project manager, without considering the needs and expectations of the receiving organization.
Therefore, the most appropriate and professional action for the project manager to do is to request that the receiving manager issue a change request to prolong the project by two weeks, and then follow the change management process to handle it. This way, the project manager can ensure that the project is delivered in accordance with the agreed scope, quality, and stakeholder satisfaction.