Interesting, but that's how and when they tell their customer base about the products. Not the ordering system itself.
I can see why you say that, but its not true. The EIPs refer to XML specifications, the "development process", and specifically mentions "... files are intended for CP technical teams responsible for designing and building the B2B interface into the Openreach gateway"
The EIPs really do document the change-control process relating to the API between CPs and Openreach - which is effectively "the ordering system".
Some of the items can be listed, for example, as "build only". That seems to imply that the new part of the interface is being developed, but isn't going to be tested or deployed. I guess that is probably the equivalent of just letting the CPs know, without making it orderable. It looks like this happens to a small subset, with testing and deployment left to a subsequent release.
The whole sequence speaks to me of a software development process, with releases every 2 months ... and functionality being added in phases.
I've never noticed a footnote like the current one.
It is certainly unusual...