This is a diagram I have created to illustrate a potential life cycle for a User Story, as well as how the Agile planning levels relate to the clarity of a User Story at different stages.
The italicized text attempts to answer the question “When does this phase typically happen?”
As in all things Agile, there is no one size fits all solution, so you’d need to tailor this to your organization and your team. My contention is that most User Stories go through all of the phases/levels whether you consciously realize it or not.
You can also download a PDF version of the diagram.