It starts tonight. Not much else to say! Head over to the official site and you can download the client software installer before the whole thing goes live.
Square-Enix is changing things up with how they handle the different regions very soon, so make sure you pick the right region.
Update: The open beta is postponed because they came across 'critical bugs'. No new release is available right now, and the download of the installer will be suspended later today.
Source: FFXIV Official Site
via Official Twitter
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