Mass Delete of Position's Valid Grades

Content

Hi.

I am required to realign the organisational grading in work that involves changing the the grade ladder and the entry grades of all the positions.

To do so i need to remove the old position's Valid Grades so the only new grade values will be updated on the Valid Grades as well.

Is there an easy way to clean all valid grades or an HDL that can remove them (but not the position record itself)?

Thanks for all the helpers.
Ben.