With MRP type P.D which firming indicator is recomended

Hello

Please Guide

I am using MRP type P.D for a material in material master for which Planning time fence field is mandatory.

1) Now i want that this planning time fence should not be mandatory.

2) Kindly aslo explain the Firming type indicators 0, 1, 2 ,

3 ,4 & which firming types are recomended for MRP type P.D.

Please Reply , itz very important.

Regards

Rahul

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