A post on XSEED's Facebook page explains that RF4 is selling "well beyond our expectations, so we're working as quickly as possible to restock physical copies." The post also thanks fans for making the game a "major success."
While waiting on a restock might be annoying, at least North American fans were spared from getting their hopes up for nothing. In Europe, Rune Factory 4 was planned to be published by MarvelousAQL, but the release was canceled in January. At the time, Marvelous stated that securing RF4's release for Europe was "not possible to do."