NIS America has dated A Rose in the Twilight:

We are happy to announce that the puzzle platformer A Rose in the Twilight(originally released in Japan as Roze to Tasogare no Kojou) will be coming to North America and Europe in Spring 2017 on the PlayStation®Vita as both a physical and digital release, as well as on Steam®!

In North America, the Standard and Limited Edition will be available exclusively on the NIS America Online Store. In Europe, we will only have a Limited Edition version of the game, and it will be available exclusively on the NISA Europe Online Store.