Some Taylor Swift fans who jumped the gun by pre-ordering a mystery celebrity book before its subject matter was revealed were surprised when it turned out to be a memoir by superstar Korean music group BTS.

Speculation of a Swift memoir was sparked when Macmillan, an imprint of publisher Flatiron Books, announced in early May that a big celebrity would be releasing a book this upcoming July.

Initially listed only as "4C Untitled Flatiron Nonfiction Summer 2023," enough Swifties pre-ordered that it shot to the bestseller position on Barnes and Noble and Amazon.

Many Swift fans got their wires crossed thanks to a number of supposed hints that ended up being unrelated to the book release.

For one, many noticed the book release date (July 9) was very close to the release of Swift's next re-recorded album, Speak Now (Taylor's Version), which is out July 7.

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"My version of Speak Now will be out July 7 (just in time for July 9th, [if you know you know])," Swift shared in her announcement, unwittingly fueling speculation that the July 9 book release date was for her own memoir.

Additionally, the total number of pages reportedly included in the book, 544, add up to Swift's favorite number, 13, when tallied individually.

Plus, there was a rumor the book’s subject matter would be unveiled on June 13 — again, Swift’s lucky number.

In a twist, it turned out the book is actually a memoir from BTS members RM, J-Hope, V, Jin, Suga, Jungkook and Jimin, who wrote the book alongside journalist Myeongseok Kang, according to CNN.

The book is called Beyond The Story: 10-Year Record of BTS and will focus on the history of the award-winning global music group.

Likely due to mounting fan confusion on social media, the publisher announced the book early — more than a month before its originally intended June 13 unveiling.

Both June 13 and July 9 are significant to BTS.

The band released their debut single on June 12, 2013, while July 9 will mark the 10-year anniversary of “ARMY Day,” which celebrates the group’s fanbase.

Beyond The Story: 10-Year Record of BTS hits bookshelves July 9. It will undoubtedly be a best-seller for the history-making group.

See some reactions to the fan confusion, below:

BTS' Early Years: Photo Gallery

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