Check all the Business Units when promoting a Supplier as Spend Authorized

Summary:

We have a Business Case wherein Suppliers are registering themselves as Prospective Suppliers with the Holding entity, using the External Registration Link. Once the internal checks are completed, a few selected Suppliers are then promoted to Spend Authorized. During this time the Business wants that all the Business Units should be auto checked rather than the Employee selecting them one by one. Currently, we have more than 25 BU's which are being handled by a single business user and checking each BU manually is a time consuming activity.

Is it possible to make all the BUs defaulted when such Promotion is happening, or is there any workaround to ensure that the Supplier is available for all BU's.