Board Thread:Questions and Answers/@comment-89.187.164.208-20200618235008/@comment-6697950-20200619143638

Yes. The web novel began its serialisation nearly a decade before the story was taken up for official release. So, by the time SAO started getting published, SAO's timeline had got too close to the present day and thus the author decided to add an extra ten years to all the events. Various other changes were made in the transition from web novel to light novel format.