Skylar Moody, 24, said she spent most of Thursday trying to avoid “Now and Then” spoilers. A superfan whose social media presence is almost entirely devoted to all things Beatles, she wanted to record her reaction to her first listen, which meant waiting until she was finished with work. She kept her phone on silent all day, lest she accidentally hear a snippet of “Now and Then” while scrolling online.

Ms. Moody, who lives in New Jersey and goes, fittingly, by @lucyinthesky.lar on TikTok, said she became a Beatles fan after watching “A Hard Day’s Night,” the group's 1964 film, during a music history class in high school. She described the Beatles’ online fandom as “very diverse and also unified.”

“No matter what age or demographic you’re in,” she said, “we can all come together in one agreement that we love the Beatles.”

She continued: “This is where we find our people now. It’s so easy to go on social media and find a fan community of people to talk to that will understand you.”

Late on Thursday afternoon, she made a reaction video of herself listening to “Now and Then” in her car. “I’m listening to the Beatles! In 2023!” she exclaimed, clutching her face through a two-minute clip in which she describes what she's hearing.

The Beatles’ company, Apple Corps, has billed “Now and Then” as the group’s “last song.” It’s the third Beatles release since John Lennon’s death in 1980, after “Free as a Bird” and “Real Love” in the mid-1990s. All three were built on home demo recordings made by Mr. Lennon.