users with office 365 E5 license can access the planner premium

I have a question if users with office 365 E5 license can access the planner premium but not all of its features? or they can not have any access at all? i read this documentation 

https://learn.microsoft.com/en-us/planner/understand-planner-trial-and-license-assignments 

but i felt a bit confused? if Office 365 E5 users can access some features of the Planner Premium? or they can only access the standard planner, can anyone explain this in more details? the license requirements for planner premium?

Thanks