This is all I could find right off.

Beta phase 2: From Friday, April 4, 2014 (JST) to Monday, April 7, 2014 (JST). Source
During beta test phase 2, players have the option to participate using pre-existing characters Source
Users currently playing FINAL FANTASY XIV: A Realm Reborn on PlayStation®3 are eligible to upgrade to the PlayStation®4 version starting April 11, 2014. Source

From the sounds of it we get teased for a weekend and then have to go back to PS3 for 4 days, then we can upgrade for early access.