Mercedes boss Toto Wolff believes that teams still developing their current car will need "a magic wand" to avoid being at a deficit next season with their 2022 designs.
At Silverstone, Wolff suggested that Mercedes had implemented the final updates of the season on its W12, a package in the works for several months, with all its engineering resources now focused on next year's contender.
However, arch-rival Red Bull has hinted that it could continue the development of its RB16B given it and Max Verstappen's unique opportunity to steal the world title from Mercedes.
But sustaining its car's development could set the Milton Keynes-based outfit back for several seasons reckons Wolff.
"You need to look also in 2022,” Wolff told Motorsport.com. “Because unless you’re having some magic wand, you will be at a deficit next year.
“So I believe that most of the teams have stopped development for 2021.
“But if they continue to push for 2021, that certainly is going to give them an advantage [this year].”
Red Bull team principal Christian Horner downplayed the team's focus on 2021, insisting that running parallel development programs was nothing new, even if next season's design will prove all-important given F1's regulation overhaul.
“You’ve got to go week by week, race by race and I think the team’s doing a great job of balancing the challenges of this year and next year,” said Horner.
“It’s nothing new. I mean there’s a lot being made of it at the moment, but we’ve had big regulation changes in the past so you have got to balance your resource and apply it to what needs the most.
“I think the team are working incredibly hard, extremely well and effectively.”