Why doesn't floor goals work with the fitbit charge HR?

So I got myself the new fitbit charge HR and wanted to set up a goal to go up a certain number of floors a day, but when I try to create a goal based on that it says that floor goals only work for the fitbit one or the fitbit ultra. The charge does have a floor counter though, so I just wanted to know if it was the text that was out of date, or something peculiar with the API.