A staggering 50 members of Mercedes' F1 engine division is switching allegiances to the new Red Bull Powertrains operation.

That is the news from the highly authoritative Auto Motor und Sport, as it published details of Red Bull's impressive preparations to take over from departing engine supplier Honda after 2021.

"They have already ordered seven test stands," revealed correspondent Michael Schmidt. "The poaching from Mercedes is more delicate. Six names have already been revealed, and six more are a done deal.

"But Christian Horner believes that around 50 Mercedes employees will switch sides by the end of the hiring process, and Andy Cowell should be among them."

Indeed, Red Bull team boss Horner told Autocar that Mercedes staff are interested in taking the "leap of faith" to Red Bull because the project is "exciting".

"I think people have seen how and what Red Bull has done in motorsport and the commitment it has," Horner said.

"It's based in the UK, it's 30 miles from Brixworth, they don't need to move house or move their children from school and it's a chance to be involved in something from scratch."

Not just that, the tantalising involvement of a Volkswagen brand - either Porsche or Audi - is also a major draw.

"We're open to working with any OEM or technical entity," Horner admitted.

"We're extremely keen to have the engine fully integrated into the chassis side of the business, hence this investment. It would be very much getting involved with our entity rather than doing something different."

And he says Toto Wolff may one day rue his decision to say 'no' to supplying Red Bull with a competitive Formula 1 engine.

"We need a competitive engine, and this is the best route," he said.

"Mercedes wouldn't supply one and Renault didn't want to supply one, so it didn't leave us with a lot of choice. We've got to get on with it and make Toto rue that decision.

"Maybe one day he will need an engine from us!"