Since the contents of the ARR CE were only announced a few months before release, maybe it will be the same with the PS4 version. Yoshi-P said ARR for PS4 should come out "Early 2014". That might mean first half or first quarter, so maybe December or January would be the earliest we could expect an announcement? That's 6 months away.

PC ports often don't have special CEs, but they can include DLCs for the same price. Maybe the first expansion will hit around early 2014 as well, and PS4 gets that as part of the release? (like FFXI + Rise of Zilart for its NA/EU release.) Plus Sony may want royalties for each PS4 copy sold.

It seems more likely to me that SE will need to charge for the PS4 version, even for existing customers.