Story DLC of the Premium Edition?

[Civi]

The Premium Edition of the game also contains the first story DLC.

Is the first story DLC already included in the game or will it be delivered much later?

If it is already included in the game, how big is it? Is it a kind of mini DLC that doesn't justify the extra cost of the Premium Edition or is it a really extensive story expansion?

[wasabi™]

It's due to be released later on, there's no information on it at this stage other then the name, "The Order of The Giants".