Answer
The version segment in the URL path (v1) is fixed and controlled by the platform framework — it can't be changed, and you can't deploy two different implementations of the same projection into one installation at the same time. If different interface versions genuinely need to coexist, the practical approach is renaming the projection/endpoint itself for the new version (giving it a distinct name in the URL) rather than trying to version the same endpoint name via the URL path.