According to the PMBOKGuide, the project manager should analyze the impact of the developers' resignation on the project scope, schedule, cost, quality, and risk, and inform the relevant stakeholders about the situation and the possible options to address it. This is part of the Manage Team process, which involves tracking team member performance, providing feedback, resolving issues, and managing changes to optimize project performance. By analyzing the impact and informing the stakeholders, the project manager can facilitate collaborative decision making and ensure alignment of expectations and objectives. References:
(Professional in Business Analysis Reference Materials source and documents)
* PMBOKGuide, 6th edition, Chapter 9, Section 9.4, Manage Team
* PMP Exam Prep, 10th edition, Rita Mulcahy, Page 357, Manage Team