Migrating OIOUBL volumes to Nemhandel PINT, and the dual-run window

Nemhandel BIS 4 finally moving forward is good, but the migration window is going to be painful for anyone running large OIOUBL invoice volumes today. The PINT architecture is fundamentally different from how OIOUBL 2.1 has been profiled, so the temptation will be to dual run during the November 2027 to May 2029 window. Two practical concerns. First, the release candidate window is only about six months, which is tight for SAP customers running customised IDocs. Second, the initial scope is only invoices, credit notes and invoice responses, so anyone using the wider Peppol BIS document set today (catalogues, despatch advices) will need to keep parallel pipelines running for at least another transition period after.