The vast majority of solutions have multiple projects, and it's common for developers to want to keep all projects using the same version of the package across all projects.

There are design questions:

• If update is run on a project that has CPM enabled, should update fail and tell the customer to only use update on the solution, so that update will check all projects for preview restore errors?
• If update is run on a solution not using CPM, and one or more projects restore successfully, but one or more fail preview restore, should update save the successful projects, or not save any of them?
• If a solution contains one or more projects that can't be evaluated, should update skip those projects, or fail early?