Paul McCartney reflected on his childhood, young love, and memories of his late Beatles bandmates John Lennon and George Harrison during a secret event at Abbey Road studios on Tuesday. The Beatles legend, 83, stunned a lucky group of fans at Studio One – where the Fab Four recorded songs such as “Yesterday”, “Penny Lane” and “Sgt Pepper’s Lonely Hearts Club Band” – when he turned up to a playback of his forthcoming album, The Boys of Dungeon Lane . There was a hushed reverence amid the 50-strong crowd as they waited patiently, not certain but perhaps having guessed that McCartney himself might make a surprise appearance at the event. As a familiar voice could be heard from a booth upstairs, heads whipped round as though watching match point at Wimbledon: “That was Paul!” Sure enough, McCartney made his way to the floor, taking a seat next to an acoustic guitar. For the next 90 minutes, he regaled the audience with stories behind the 14 songs on his 21st solo album, due for release on 29 May.…