According to the PMBOK® Guide, the project manager is responsible for leading and directing the project team and ensuring that the project objectives are met. Therefore, the project manager should not delegate the decision-making authority to the team or the sponsor without analyzing the impacts and creating a plan for team decision making. The project manager should also consider the risks, issues, and stakeholder expectations that may arise during their absence and communicate the plan to the relevant parties. Postponing the vacation to a different time may not be feasible or desirable for the project manager, and it may also affect their work-life balance. Allowing the team to make decisions to stay on schedule may result in scope creep, quality issues, or conflicts among team members. Asking the project sponsor to make any necessary decisions may undermine the project manager’s authority and credibility, and it may also burden the sponsor with additional work. References: PMBOK® Guide, Sixth Edition, Chapter 9, Section 9.4.2.3 (Team Decision Making) and Chapter 13, Section 13.3.2.4 (Project Manager)