The availability of music on Spotify is up to the artist and their music label.
Spotify has no control over what content is available.
Spotify will have the album as soon as the record label is ready to release it to them.
Tyler, the creator's new album 'Cherry Bomb' is due to release on April 13, 2015.
If the artist and/or label allow it on streaming service, it should reach Spotify soon.
And it's now available :)