We will be making the current experimental version (3.23) the new release version on or shortly after Nov 17, 2015. The versions will then be:
3.21 will be deprecated and you will be served an existing version.
If you are using a Maps API for Business client ID or you are on the premium plan, you will be provided with the release version by default. If you are on the standard plan or have no key nor clientid, you will be provided with the experimental release by default.
For more information about Maps API versioning, see:
To report issues with any version of the API, see: