Send Dunning Letter without BU

Summary:There is requirement in which we need to run a Send Dunning Letter program ignoring BU(For a customer all records should come irrespective of BU). Technically how to achieve it ?

Content (please ensure you mask any confidential information):There is requirement in which we need to run a send dunning letter program ignoring BU(For a customer all records should come irrespective of BU). Technically how to achieve it ?

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