After Supplier Merge - manual changes to Address site levels?

After a Merge, Is it necessary to uncheck Purchase, Pay sites and then mark it Inactive at the Address site levels on the old supplier? I am on R12.       1) Currently, after a supplier merge, we go into the inactive supplier's address site level at both the manage site and update areas to uncheck the Purchasing and Pay sites. Then we go into the update field to make change it to inactive.

2) Sometimes it does NOT mark the supplier (in the Organization area) with a date in the Inactive Date field. Why?