What Causes Suggested Due date does not equal to the Consumption Start Date for Buy Item's

Summary:

We'd like to understand the calculation of the Suggested due date in constrained planning. What are all the factors that cause the Suggested Due date does not equal to the Consumption Start Date for Buy Item's planned orders.

Content (please ensure you mask any confidential information):

We use supply plan with constrained planning. We understand that the safety stocks may cause the Suggested Due Date does not equal to the Consumption Start Date for Buy Item's planned order.

As per our test, we also found that the Minimum Order Quantity, fixed Order quantity and Fixed Days of supply also have impact to the Suggested Due date calculation. These planning parameters cause the Suggested Due Date are one week to 2 months earlier than the Consumption Start Date for Buy Item planned orders. This behavior causes high inventory value. Should these planning parameters only impact planed Order quantity and does not impact the Suggested Due date for buy item planned orders.