Cross-over play from PC to PS4 when released?

[Markise]

The billing system can be setup for many complex arrangements, but most people use the simplest case: One platform (PC), one set of characters, one monthly fee. To add another platform (PS4), you just buy the software and add the registration code to your existing FFXIV Service Account. Then that set of characters can be played on either platform (but not logged in simultaneously).

Thanks for the clarification I appreciate it. Just wanted to make sure if I was to buy it for both I could use the same characters etc.