The performance version of the luxury limousine has been spied undergoing what looks like final testing, given a lack of camouflage or body cladding on the test mule snapped in our high-res image gallery. The face looks more aggressive than the stock A8 but rather subtle and still tastefully elegant, with bigger wheels filling the wells and larger brakes in turn filling the wheels.
But, of course you want to know what's under the hood. Don't we all. Following a similar trajectory to arch-rival BMW's latest M5, word on the street is that the Lamborghini-derived V10 from the previous S8 will be replaced by the new twin-turbo V8 expected to find its way as well into the new S6, S7 and Bentley Continental GT. Output and efficiency are expected to increase, however, with power ratings mooted in the 500 horsepower range.
That's a lot of beef, and if we had to guess, we'd say we'll probably be scoping it out in person come September's Frankfurt Motor Show.