Q.  Why is MRP giving me demands for the past?

 

A.   If the demand falls after the systems last calendar date, MRP will default the demand to the 1st day within the calendar date.

For Example:  If your First System Calendar date is  01-01-2002 and your Last System Calendar date is 12-31-2007.

You create a SO with a delivery beyond the last calendar date of 12-31-2007,  MRP cannot calculate the correct date so it will default to the first calendar date of  01-01-2002.  Once the system calendar is updated and MRP is re-ran the demands should be correct.

User does receive several warnings when saving the SO that the calendar in System setup needs to be updated.