Undefined includes this bullet point at the end.
You can always switch from the fast-4.14 channel to the stable-4.14 channel. There is a possible delay of up to a day for the release to be promoted to stable-4.14 if the current release was recently promoted.
That timing is incorrect and we should just forego setting expectations.
After your version has been promoted to stable-4.14 channel you may switch to that channel.