But that's also count to Invisible.
As for the Invisible release date there are many sources, that shows that this song was available in May 10th.One of that source is Shoutbox. If you check archiwum of the shoutbox (May 10th), someone post link to the song on iTunes (I think it was me), every individual song on iTunes released before the whole album, is sold from the same barcode (individual barcode assigned to this song only) like the other stores have. Here are two other sources of Invisible release date: http://mora.jp/package/43000008/054391958143/ https://s18.postimg.org/69u7mpl2v/Untitled-1.jpg