Top Beatles historian Mark Lewisohn believes that the group didn't enter into their 1969 sessions for Abbey Road believing they were producing their swan song. Abbey Road is set for a deluxe and expended 50th anniversary reissue on September 27th.

Available now is Mark Lewisohn's complete unedited version of his groundbreaking 2013 first volume of his trilogy on the group, All Those Years, Vol 1 - Tune In. In addition to writing the definitive books on the Beatles' live concerts from their Quarryman days up through their final Apple Rooftop performance, Lewisohn -- at the behest of the Beatles' label EMI -- listened to the band's entire tape archive, which was documented in his 1988 book, The Complete Beatles Recording Sessions: The Official Story Of The Abbey Road Years.

During a chat with Mojo, Lewisohn said that the "Fab Four" was not looking at Abbey Road as a farewell: "They mention their break-up, in casual conversation (during the early-1969 Let It Be film shoot), without any kind of emotion -- as if they've already discussed it. But when they were making Abbey Road I don't believe they thought it was the last time. No one knew they were in any kind of trouble. Although they had lost some approval ratings here in Britain. There were complaints about them, largely emanating from Fleet Street. (Abbey Road) went on to be Number One (In England) for 18 weeks. That's the ultimate vote."

Lewisohn went on to say that Abbey Road stands as a testament of modern record making: "I think it's the one that's most attuned to modern ears, the one that could least be least described as old-fashioned. Abbey Road -- it's a rock album, and while rock has changed a lot in the last 50 years. . . It sounds contemporary."

Mark Lewisohn told us that to truly get to the bottom of the Beatles' story, one needs to reexamine every instance of the group's journey to find the real truth as it happened: "People always take the Beatles' point of view on everything. It's time to look at this story from all sides now -- and not just the Beatles' own point of view, and to dislike the people they disliked, and to hate the people they fell out with, or who may or may not have wronged them. The truth is a wider story than that, and it needs to be looked at properly."

AUDIO: MARK LEWISOHN ON TELLING THE BEATLES' STORY TRUTHFULLY