The song was released digitally only in Japan at the moment, but FF staff confirmed it will be available overseas soon enough.
Also, another song seems to be about to be released in the next few days.
iTunes
https://itunes.apple.com/jp/album/id1449799743?app=itunes
Mora
http://recochoku.jp/song/S1007656373/
Recochoku
https://mora.jp/package/43000001/4547366397185/