Section 6.11 is out of date and incorrect

Section 6.11, "Concurrent API versions", of WD18 () describes a mechanism for supporting concurrent API versions that does not agree with Section 2.3, "Versions and Extensions", Section 5.5, "PlatformEndpoints Resource", and Section 5.6, "PlatformEndpoint Resource". Since the later were added after the former, it is pretty obvious that the material in Section 6.11 should have been cleaned up as part of the resolution of the issue(s) that resulted in the creation of Sections 5.5 and 5.6.