Taylor Swift has been full of surprises lately. On April 12, she got fans in a swirl by posting on Instagram that she’d be dropping an unnamed and unexpected cover single on Spotify, along with an alternate version of her latest single, “Delicate.”

Swift doesn't tackle covers often—at least, not put down on record in the studio—so it stands to reason that just about anything she'd tackle would be news. However, she really shocked fans when her choice was revealed: The 1978 soul/funk classic "September" by Earth, Wind & Fire.

This, of course, is one of the most recognizable jams in music history (as anyone who's ever attended a wedding reception will well know). Swift managed to put a highly personal slant on the song, however, turning the dancefloor classic into a stripped-down, country-tinged, banjo-laced exercise.

She even added a fun and very Taylor touch by changing the line “Do you remember the 21st night of September?” to “28th night" —which may confuse the average listener, but that hardcore Swifties quickly identified as the starting date of her relationship with boyfriend Joe Alwyn.

Overall, the song has strong enough bones to endure even a total 180-degree genre change, and it's undeniably a lyrically romantic tune that's right up Swift's alley. However, reaction was prompt on social media, with many expressing outrage that Swift would mess with a beloved classic completely out of her wheelhouse.

Still others felt the song was a fun exercise in dipping into her Nashville roots, something Swift has been indulging in of late. She recently joined Sugarland for a duet on the duo's new album, Bigger, for the track "Babe," a track she co-write with Train frontman Pat Monahan.

And of course, there's her song "Better Man" performed by Little Big Town, which led to a Song of the Year win at the 2017 CMA Awards (and a Best Country Duo/Group Performance prize at the 2018 Grammy Awards).

She also made headlines recently for a surprise appearance at the Bluebird Cafe. Her March 31 popup performance included acoustic deliveries of her hits "Love Story," "Shake It Off" and "Better Man" as part of a documentary celebrating the venue's 35th anniversary.

What do you think of her EWF redux?

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