Square Enix have announced that both Kingdom Hearts Birth by Sleep and Kingdom Hearts Birth by Sleep Final Mix will be re-released in Japan as Ultimate Hits editions. Both items have been added to the Square Enix e-STORE, with Birth by Sleep here and Birth by Sleep Final Mix here. Both cost ¥2,940 (approximately US$37.91) and release on December 6, 2012.
When Square Enix considers a game to be very successful and have sold enough copies, they reprint the game as an "Ultimate Hits" edition-- this is the exact same game with an altered cover art and new price. All Ultimate Hits titles can be seen here.