I should structure the response to cover both user-facing steps and the technical aspects. Maybe start with a user guide, then outline backend considerations, and include additional features like reminders or notifications. I need to make sure the explanation is clear and covers all possible parts, not just a single aspect. Also, considering security is important for payment processes. Let me check if there are any other features commonly included in such updates, like cancellation options or downgrade paths. Including those might be helpful.