Receivables Upgrade to R12 and Advanced Collections
As per Oracle documentation, "A limited version of Oracle Advanced Collections functionality is available in Oracle Receivables and replaces the Receivables Collection Workbench. Receivables users who have not purchased a license for Advanced Collections are not authorized to use the full feature of this product."
"If you have used dunning functionality that was offered in a previous version of Receivables, then you can access those historical dunning letters by using the Dunning Letter Reprint - Historical Receivables Only program. This program reprints individual dunning letters that were created in earlier versions of Receivables, before the integration with Advacned Collections."