Simon & Schuster told the New York Times that it accelerated publication by several months because “the book is now ready.”

Isaacson, chief executive of the Aspen Institute and author of biographies on Benjamin Franklin, Albert Einstein and Henry Kissinger, has conducted more than 40 interviews with the Apple founder and others for “Steve Jobs: A Biography.”

Isaacson told Fortune that the new publication date is not “related to any decline” in Jobs’s health. “I turned most of the book in this past June. It’s now all done and edited. The March 2012 date (or whatever date it was) was never a deeply-considered pub date.”

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