The project manager should perform iterative planning with the team to use the prototype, as this would allow them to adapt to the changing situation and deliver value incrementally. Iterative planning is a technique that involves breaking down the project scope into smaller iterations, each with its own plan, deliverables, and feedback loops. This technique enables the project team to respond to uncertainties, risks, and changes more effectively, and to incorporate lessons learned and stakeholder feedback into the next iteration. In this case, the project manager can use iterative planning to align the team with the new solution, define the requirements and acceptance criteria for the prototype, and monitor and control the integration and testing of the prototype.
References: (Professional in Business Analysis Reference Materials source and documents)
* PMBOK Guide 7th Edition, page 67, section 3.2.2
* PMI Agile Practice Guide, page 33, section 3.2.1
* PMI Professional in Business Analysis (PMI-PBA)Examination Content Outline, page 14, section
3.3.1.1