That I'm not sure of I'm sorry, they may put it up for preorder on the store as they did for LBP Vita or LBP Karting which included their preorder costumes, but not sure if that will be the case for this one.
Considering Cross-Buy is involved, they have to have at least the Vita version digitally available day one. And of course the PSBlogs confirmed it at one point, too. Expect most Sony games to end up on PSN day one in the near future.
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