Update: Added 12 additional photos of this test mule to a new gallery, available below.

New spy photos have captured a heavily camouflaged Audi sedan out testing. A close inspection of the images reveals the four-door with some suspiciously wide fenders that, paired with the news that Audi will rejigger its lineup nomenclature, muddies the waters on which future model this is.

Underneath the camouflage appears to be a fairly standard Audi S6. However, the wider fenders might suggest an even sportier powertrain hides beneath the sheet metal. Our sources believe this is the next-generation RS7, but Audi only offers the current model as a liftback, and the car in the spy shots is clearly a sedan.

Gallery: Audi RS7 Test Mule Additional Spy Photos

Audi confirmed earlier this year that it would rearrange its lineup. The A4 will become the A5, and the future A6 will become the A7, allowing the automaker to use even numbers to designate EVs and odd ones for cars with combustion engines. Audi plans to launch around 20 new cars by 2025, with over half being electric vehicles.

The next-gen Audi test vehicle also sports a unique dual exhaust system that doesn’t look like the standard pipes of any model. Audi also covered the taillights with additional camouflage, unlike the vehicle our spy photographers captured in early May. The new exterior should coincide with a revamped cabin with more screens and the latest technology and safety features.

Gallery: Next-Gen Audi RS7 Spy Photos

It’s unclear what Audi has planned for the model’s powertrain. The photos show the sedan with electrification markings, and the previous test vehicle also had a visible charge port. The current RS7 packs Audi’s twin-turbocharged 4.0-liter V8 engine that makes 621 horsepower. An electrified replacement should meet and exceed that figure, but expect a range of combustion engines with electrical assist available in the non-S and non-RS variants.

It’s unclear when we will see the A4 successor debut, but the revamped and new A6/A7 should arrive before it. The current-generation A6 launched for the 2019 model year and is due for a thorough makeover. The spy photos have captured a car in the early stages of its development cycle, so it might not break cover until sometime next year or arrive in the US until 2025.

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