The date fields on order and order proposal lines are calculated as follows:

On a purchase order line, the Order Date + Lead Time Calculation = Planned Receipt Date.

On a production order line, the Starting Date + Lead Time Calculation = Ending Date.

Note
The program normally uses the routing to calculate a production order ending date. The lead time calculation is only used if the item does have a routing.

Concerning transfer orders, an item's lead time calculation is not included directly in the calculation of the transfer order receipt date. However, lead time calculation could influence the receipt date of a transferred item as it will affect any replenishment order (purchase or production) at the transfer-from location before the transfer begins. For more information, see Planning with Manual Transfer Orders.

The Lead Time Calculation field appears in other tables. The program will prioritize the field first on the item vendor card, then on the stockkeeping unit card, and last on the item card.

Reference