According to the PMBOKGuide, the project manager is responsible for managing the communication among stakeholders, and ensuring that the information needs of the project are met (Section 10.1). The project manager should also establish and enforce the ground rules for communication within the project team, and address any issues that may arise from unauthorized or inappropriate communication (Section 9.3.2.4). By pointing out to the project team and the customer that all information concerning the timeline of the project should be communicated by the project manager, the project manager can prevent confusion, misunderstanding, and conflict among the stakeholders, and maintain control over the project scope and schedule. This is also consistent with the Professional in Business Analysis (PMI-PBA)Examination Content Outline, which states that one of the tasks of a business analyst is to "communicate requirements information to stakeholders according to the communication plan" (Task 4.3). References:
* PMBOKGuide, 6th Edition, Section 10.1, Section 9.3.2.4
* Professional in Business Analysis (PMI-PBA)Examination Content Outline, Task 4.3