Alias Email Business Unit Mapping in Invoice Image Documents Stream

The 26C release notes state that the Alias Email Business Unit Mapping feature allows a Business Unit to be associated with an alias email address for automatic Business Unit defaulting on unmatched invoices.

In our environment, the alias email configured under Capture > Document Receiving Endpoint > Aliases is displayed under Streams > Invoice Image Documents > Email Aliases. However, we do not see an option to associate a Business Unit with the alias email address.

Has anyone successfully implemented this feature? If so, where is the Business Unit mapping maintained, and are there any prerequisites or additional configurations required to enable it?