According to the PMBOK Guide, 6th edition, one of the key skills of a project manager is to negotiate with stakeholders to achieve project objectives and balance the competing project constraints. Negotiation is also a tool and technique for the process of Manage Stakeholder Engagement, which aims to ensure that stakeholders' needs and expectations are met or exceeded. By engaging in creative and iterative negotiations with the leaders of each entity, the project manager can foster collaboration, trust, and commitment among the parties involved in the project, and ensure that the launch date is acceptable and feasible for all. This will increase the likelihood of timely and successful adoption of the new solution by the entire organization.Reference: PMBOK Guide, 6th edition, pages 53, 513-514, 518.