Talent Upgrade - Do we need to convert existing data after the upgrade processes are completed

Summary

In the process now of upgrading to new Talent Profiles. I am unclear from the documentation whether the content items and all of the data is converted during the process

Content

In reviewing the documentation for upgrading to the New Talent Profile, I am having a difficult time finding if when the upgrade processes are completed, should our existing data already be available.  Or do we need to add content items and reconvert all of the data.  It is not fully clear whether this needs to be done, as there are instructions on loading data, but I am not sure if it is expected that we would need to do this.