Presumably, it just falls under the general "performance and stability enhancements" item in the release notes. But yes, calling this out specifically might be a good idea. There is, as far as I've seen, no formal process for doing this, but usually staff note important changes in the reless notes (like they did for the major Z-Wave changes or like they do when a platform firmware version intoduces a database or app incompatibility problem if you roll back and don't take the FB with you).
But in this case, you didn't really lose any features. The default just changed. You can change it back--or set it to whatever you want--by doing the following: