Non breaking changes will be incorporated into production versions immediately. Users will not have to do anything on their end to get non-breaking changes. Breaking changes, however, will be put into a public preview in next year’s version, which can happen immediately. We do not have to wait for next year in order to release public preview APIs. Once we enter the next year (exact dates TBD), whatever is in public preview will become public.
Release notes are a good idea and @tyler_mairose has been working on a solution that can help expose the differences between two versions of APIs. This is something that we will continue to work on to provide our users with the information they need.
API consistency and adherence to our API guidelines is an ongoing effort. As of now, v2024 is simply a copy of v3 which is why it contains all of the inconsistencies. As the years progress, we are hoping to close the gap and make our APIs more consistent.