Timing of the Cutover strategy review
The first review of the cutover strategy should be conducted as part of the Solution blueprint review or soon afterward. It might be tempting to postpone the cutover strategy review because it can be perceived as an activity that happens at go-live. However, cutover includes the touchpoints from data migration and rollout planning, and it's a process that starts at the early review of the vision, scope, and strategy. The overall project plan for cutover helps the project to anticipate and manage risks.
The detailed cutover plan would not be ready in the early stages; therefore, you should review it at a later stage so that you can identify risks in enough time to remediate them. During the Implement phase, and for more complex cutovers, you should plan a key milestone review, which involves reviewing the status and issues that arise from a key mock cutover. Make sure that you conduct this milestone review before user acceptance testing (UAT) environment and data preparations are complete. This approach will help the project team identify risks and address them so that the environment that is created for UAT is a close approximation of the process by which the production system will be created after the final cutover.
As the project approaches go-live, make sure that you review the readiness for the final go-live. This process involves reviewing the risks that are associated with the following elements and then ensuring that they can be resolved:
Business activities prior to go-live are identified, communicated, and are on track
Data quality from source systems through to Dynamics 365 is understood in depth and is adequate for effective use in production after the final cutover
Issues from mock cutovers have been addressed
Readiness of the detailed cutover plan and resources is in place
Readiness of the communication channels and messages for the teams during the cutover has been defined