Heavensward - Buying expansion once or twice for PC & PS4?

[Syrellaris]

There hasn't been an official response. Yes, when discussing the topic of buying the game license per platform, but not for an expansion. You already own the game -- the expansion is an EXPANSION of the game that you've purchased. I am not stating this as an official response, but I would hazard that you would only buy the expansion once.

There has been an official response, not perse about Heavensward but about FFXIV in general. The same buying method still applies to heavensward. You need a Game code(key) for each platform you play on.

Btw, just buy 1 collectors edition and then purchase a cheap 5-10 dollar License code for the ps4 instead of buying two games.