When you assign resources to a task, Microsoft Project assumes by default that each resource begins working on the task on that task’s start date. But that scenario might not match reality. One resource might begin work on the start date, but another might not be available until several hours or days later.
With Microsoft Project, you can specify exactly when a resource begins working on a task. For example, you can stagger the times that multiple resources begin working on the same task by delaying the starting time of one or more of the resources. This is true even if you have only one resource assigned to a task. When you delay the start of a resource assignment, Microsoft Project recalculates the start date and time for the resource’s work on the task.
To control when a resource works on a task
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