Solution : https://service.sap.com/sap/support/notes/523521 (SAP Service marketplace login required)
Key words :
prerequisites global variable root1, object type wbs-hierarchy, attached program correction, wbs elements, wbs structure, bapi bapi_project_maintain, 2054_project_maintain reason, implementation, note 425614, substitution
Related Notes :
| 425614 | BAPI does not execute WBS substitution/-validation |
| 363235 | EPS: WBS hierarchy allowed with several roots |