Tesla has pushed its product announcement further, with our sister publication Autocar UK’s sources predicting that it will be the arrival of the Model Y. Originally, the announcement had been scheduled for October 17, but Tesla CEO Elon Musk revealed on Twitter that more days were required for “refinement”.

Earlier this year, Tesla confirmed that it was developing an expanded all-electric line-up that would include a Model Y, an electric cargo van, a minibus and a pick-up truck. Musk's suggestion that the October debut will be “unexpected” means it could also be something entirely different.

Potential products include improved charging or road-imaging technology. Some industry experts suspect that next-generation driverless technology won't arrive for several more months and so have dismissed that as a likely candidate. More information will be released when the mystery product is launched in the coming days.

Model Y and more to lead expanded range

Exactly when the Model Y and its new siblings arrive is yet to be learned, but Musk has at least confirmed that the future models will be built upon existing chassis underpinnings from the Model 3 and the Model X. He said that the Model Y, which will be a compact SUV, will be based on the Model 3 sedan. The electric cargo van, pick-up and minibus will use the chassis of the Model X.