Symptom
There is a requirement to change the number range interval for Billing Document Requests, but Flexible Billing Document Numbering only works with Billing Documents and doesn't work with Billing Document Requests.
Environment
SAP S/4HANA Cloud
Cause
'Flexible Billing Document Numbering' is not enabled for Billing Document Requests. As a Billing Document Request is only a predecessor of an invoice it's not a legal document and therefore not enabled for 'Flexible Billing Document Numbering'. The invoice is subject to legal requirements and therefore invoice document numbers are also subject to legal requirements.
Resolution
Currently, there is no way to change the number range interval used for Billing Document Requests.
Flexible Billing Document Numbering is restricted to only Billing Documents.
However, if you believe this is something necessary for your business, you can consider creating a feature request for the same. Please refer to KBA 2963059 - How to Submit Feature Requests for SAP S/4HANA Cloud Product.
See Also
Flexible Billing Document Numbering
Using Custom Logic (BAdI) to Implement Flexible Billing Document Numbering
How to Implement Flexible Billing Document Numbering with Configurable Parameters and Formulas (CPF) – Video Tutorial
Using Configurable Parameters and Formulas (CPF) to Implement Flexible Billing Document Numbering
Keywords
Flexible Billing Document Numbering, BDR, Billing Documents Request, Number Range, Interval, Change Number Range , KBA , SD-BIL-GF , Basic Functions , SD-BIL , Billing , SD-BIL-GF-2CL , Basic Functions (Public Cloud) , Problem