Date emphasis: When to use BOTH or SHIP

Summary: We are revisiting our date emphasis used with shipment planning. We are going to be reverting back to BOTH or looking to explore SHIP. What is the difference between the two during shipment planning? It appeared that they are behaving the same in relation to time windows.

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We were planning with dates in "PAST" because we were advised that is the best emphasis to process order deletes. Since then, we have remedied that issue and are looking to change date emphasis to have better shipment start times for shipment tracking and on time performance.

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