a question about the PS3 to PS4 upgrade

The PS4 version of FFXIV:ARR is due to start beta February 22, then be officially launched in April. I've heard that current PS3 players can upgrade to the PS4 version for free, but that it's a one-way move (i.e. once you switch to PS4, you can no longer use the PS3 version).

My question is whether that "only one platform active" rule applies while the PS4 version is still in beta? Between February and April, can we alternate between the (released) PS3 version and the (beta) PS4 version, with the switch being finalized in April when the PS4 version is truly released? Or would we have to give up access to our full version of the game in order to beta the new version?

ive been curious about that aswell ;/ if it means goin through testing all over again n waiting for release on ps4 with no playing on ps3 version....id gladly just buy another ff14 xD

I think I saw it in one of the Q & A threads that to test the PS4 beta you'd have to create a new character entirely. So it's a pretty safe bet that your main char will be safe while to test on the other

Also the beta isn't tied to the paid subscription. Thus it will be available tom some (for free) even without owning the PS3 version.

Instead I am puzzled by this "one way" thing. What about if one wants to play in both PS4 and PS3 with the same character? Just think about people living in two different places (students for example). I don't see many reasons why SE after upgrading to PS4 shouldn't let people play on PS3 as well.