Lovely jubbly! Del Boy's back – as a teenager

Boycie and Marlene have fled to the countryside. Del and Rodney are probably still knocking out hooky gear from Nelson Mandela House. Meanwhile, John Sullivan, the writer of Only Fools and Horses, has been dusting off his scripts for the long-anticipated prequel to Britain's most popular sitcom – which raked in 24 million viewers at its peak – featuring a teenage Del.

Del Boy, the dodgy wheeler-dealer with a heart of gold, though knocked by life many times, never would stay down. Even when he fell through an open bar in a classic bit of slapstick that rivalled the Moon landings as the greatest ever TV moment, he scrambled up again with his cocktail intact.

While the series of Only Fools and Horses ended in 1991, Del and his motley gang of ne'er-do-wells kept popping back up on our screens in the form of Christmas specials until 2003. Now, five years after he left our screens apparently for good, it seems Peckham's favourite son is on his way back.

Industry insiders say the BBC is once again looking at Sullivan's idea of a prequel that would be set in the 1960s. Called Once Upon a Time in Peckham, the comedy would tell the story of the brothers' parents Reg and Joan, as well as a younger Grandad. Del and Rodney's mother loomed large in Only Fools and Horses, but only as backstory – she died when Rodney was young, leaving Del to bring up his little brother after Reg disappeared.

Sullivan first had the idea of the prequel in 1997, and in 2003 the BBC went as far as announcing the show had been commissioned, calling for young actors who wanted to play Del Boy to come forward. Then, the final episode of Only Fools and Horses set the scene. The Christmas special, called "Sleepless in Peckham", centred around a photograph from 1960 of the Jolly Boys' Outing, a coach trip with a young Del, Boycie and Trigger, with Reg, Grandad and "gentleman thief" Freddie "the Frog" Robdal, who bore a remarkable likeness to Rodney.

Sullivan explained at the time that the pilot episode of Once Upon a Time in Peckham would see Del Boy bunking off school, becoming a mod and flogging dodgy gear to his mates – younger versions of Boycie, Denzil and Trigger.

"I'm having a lot of fun writing it because it's set in the same period as when I was growing up," Sullivan said. "Joanie will be a key character, and during the film will give birth to Rodney. We'll also see Grandad as a much younger man."

The idea was shelved, however, and instead the BBC decided to make The Green Green Grass, Sullivan's spin-off featuring the snobbish used-car salesman Boycie and his wife Marlene, who flee to the countryside to escape the Driscoll brothers. Now in its fourth series, The Green Green Grass attracts about six million viewers per episode. Industry insiders say its success has led the BBC to dust off the scripts for Once Upon a Time in Peckham, with a view to commissioning it later this year.

A spokeswoman for Sullivan's production company Shazam, which makes Green Green Grass, said the sitcom was one of three or four projects the BBC was discussing with the writer.