These documents are considered living documents, meaning they will be updated continuously throughout the Planning Phase.
Diligent work in the Planning Phase, which often involves several iterations of plans and schedules, should mitigate risks and increase chances for success.
There may be features that satisfy more than one requirement, and it may take many features to satisfy a single requirement.
But every requirement must be traceable to its solution counterpart.
For migration projects, the conceptual design is generally identical to that developed for the current version of the application or infrastructure component.