What is the cause for the exception message "Reschedule In Operation" at the end of the MRP run?

The "Reschedule In Operation" exception message indicates that there is a conflict between the timing of planned receipts and the requirements in the system. Specifically, this message occurs when the requirement's date is scheduled to occur before that of a firmed planned receipt. In essence, it signals that the production or procurement activities need to be adjusted because the material requirement cannot be satisfied by the current firmed planned receipts due to the date overlap.

In a well-functioning MRP (Material Requirements Planning) process, timing is critical. If a requirement is set for an earlier date than when a firmed planned receipt is expected to arrive, the planning system recognizes that there is a potential issue in meeting that demand on time. Thus, it prompts a rescheduling to ensure that the necessary materials or products are available when required. This helps maintain production flow and prevents stockouts.

Understanding this exception is crucial for effective production planning, as it highlights the importance of balancing lead times and ensuring that all components are available in alignment with production schedules.