Moving basic planner to premium planner.

We're testing the new planner premium features and are unable to convert our current plans to show the new features.

We have the ability to create a new premium plans but the information on learn doesn't match what we're seeing in app on team and on the web. 

 https://learn.microsoft.com/en-us/office365/planner/plan-conversion#converting-to-a-premium-plan

We've also tried creating a Premium plan and recreating the buckets of the original plan with the aim to move the tasks to the new plan but the new plan does not show on the main list.  

Are we missing something?