A previously uncirculated tape of a 1969 discussion between three out the four Beatles shows that the legendary group was thinking about working on another studio album beyond Abbey Road, which ended up being the Fab Four’s final recorded LP together, not to mention one of the most famous and critically acclaimed albums of all time.

In a new interview with The Guardian, Beatles expert Mark Lewisohn talks about the tape—which is part of his current multimedia stage presentation, Hornsey Road: The Surprises and Delights of Abbey Road—calling the discussion “a revelation.”

The conversation in question—recorded almost exactly 50 years ago on Sept. 8, 1969, at Apple Records in London (just two weeks before the release of Abbey Road)—is between Paul McCartney, John Lennon and George Harrison and chronicles the three songwriters trading both ideas as well as thinly veiled barbs, pointing to the much-discussed fragmented relationships within the band that eventually led to their infamous breakup. As The Guardian notes, drummer Ringo Starr was unable to make the meeting due to his hospitalization for a stomach issue—the reason for his bandmates recording the conversation.

Lennon’s idea for the next album is that each of the three main songwriters bring in ideas for a single (which could’ve been released even within a few months), and that the tracks should be made up of four songs each from himself, McCartney and Harrison, with two from Starr…”if he wants them.” (Lennon also discusses how he wants the longtime crediting of Lennon-McCartney to change to individual songwriting credits.)

“The books have always told us that they knew Abbey Road was their last album and they wanted to go out on an artistic high,” Lewisohn notes. “But no—they’re discussing the next album. And you think that John is the one who wanted to break them up but, when you hear this, he isn’t. Doesn’t that rewrite pretty much everything we thought we knew?”

Furthermore, the tape provides some insight into the strained connections between the band members, as McCartney answers Lennon’s four-song-apiece suggestion by saying, “I thought until this album that George’s songs weren’t that good.” Harrison responds, “That’s a matter of taste. All down the line, people have liked my songs.” Lennon even takes a shot at one of McCartney’s Abbey Road inclusion, the goofy “Maxwell’s Silver Hammer,” hinting that he should give similar songs to other artists in the future rather than bring them to The Beatles.

Read more of Lewisohn’s observations in The Guardian‘s interview, as well as more on his live show, Hornsey Road, and his ongoing, multi-book Beatles project, The Beatles: All These Years, whose first volume, Tune In, was published in 2013.