Benefit Group (bargaining group) and related PDBAs in Employee DBA Instructions

:  Enterprise One 9.2 version.

We have benefit groups in our organization.  There are certain PDBAs which are being added automatically to Employee DBA instructions when an employee is hired.  HR does not add those PDBA's manually.

I understand there should be a relation between Benefit groups and a list of PDBAs which should be automatically assigned.  Where do I find and edit the list.

I already checked P059101 - Work With Group Plan DBA Setup  but found nothing in it.  Any help is appreciated.