Swift has released two new songs exclusively to Spotify Singles, the streaming service’s weekly playlist that focuses on two new songs from a single artist. The tracks are a new version of Swift’s Delicate, as well as an acoustic version of Earth, Wind & Fire’s September, according to CNET, which earlier reported on the move.

Spotify Singles is a series exclusive to the network that allows users to stream the two artist-chosen tracks for a week. Artists will usually choose to re-record one of their own songs in a different fashion, as well as cover a song that means something personal to them.

Swift’s participation in Spotify Singles stands in stark contrast to a position she took against Spotify years ago that the service and other streaming offerings would ultimately hurt the music business.

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“All I can say is that music is changing so quickly, and the landscape of the music industry itself is changing so quickly, that everything new, like Spotify, all feels to me a bit like a grand experiment,” Swift told Yahoo in an interview in 2014, when she removed her 1989 album from Spotify. “And I’m not willing to contribute my life’s work to an experiment that I don’t feel it fairly compensates the writers, producers, artists, and creators of this music.”

Swift kept her first four albums off Spotify between November 2014 and June 2017. Since then, she has allowed her tracks to be played across streaming services and has seemed committed to supporting them in different ways. Swift was among the first artists to appear in Apple Music ads. Her 1989 World Tour was also streamed over Apple Music.

Now, though, she’s offering an exclusive to Spotify. And once again, it appears the intense battle between Apple and Spotify is only heating up.