USER EXIT PDATE

All, I would appreciate your help to find the user exit PDATE in SCM 7.

I am planning to use the Planning Start Date field TBID_START field to dynamically recalculate a data view start date.

The SAP Help on this field identifies the User Exit 'PDATE' for this purpose.  However, I am not able to find a PDATE user exit.

Can you help to find where this exit exists.

Thanks

Chris