We're on the cusp of seeing the sixth-generation Audi A4. It's certainly time, as the current model debuted in 2015 for the 2016 model year. Amid sedan sightings, we've seen occasional Avant test vehicles out and about in both A4 and S4 trim. This time, instead of snapping photos, our spy crew clicked record for some video footage.

Multiple prototypes are spotted here, all wearing the same level of camouflage wrap. We don't see any hard coverings beneath, but placeholder taillights are still in place. A couple of vehicles feature a single-exit exhaust with twin tips, one of which emits a clear four-cylinder sound as the driver pulls away. Another test vehicle sporting dual exhaust at the corners also makes an appearance. We believe this is an S4 Avant, further supported by larger black wheels with big brakes behind them. And when it pulls away, the sound is more in-tune with the 3.0-liter V6 used in the current S4.

Gallery: Audi A4 Avant Spy Photos

Despite stricter emissions regulations coming in Europe, our sources believe the turbocharged V6 in the S4 will carry over, though it could gain hybrid assist to add power while reducing nasties in the exhaust. The A4 could remain purely internal combustion, using an updated version of the enduring turbocharged 2.0-liter four-pot tuned for cleaner emissions. However, some sources say every next-gen model will have some form of mild hybrid assist. That holds true for diesel engines as well, which are expected to return.

As for styling, the exterior will clearly take an evolutionary approach. The headlights will get thinner, the grille will get a bit wider, but it will still be easily recognizable as an Audi. Inside, you can expect plenty of digital displays, though Audi seemingly won't follow BMW or Mercedes-Benz by incorporating them into a single big screen. Recent interior spy shots reveal a tablet-style center touchscreen sitting on its own, with another display relegated to the driver.

Our spy sources feel confident that the next-gen A4 in both sedan and Avant trim will go on sale in 2023. Whether or not it's a 2023 model remains to be seen. If we get a debut before the end of the year, which is very possible at this point, it should be a 2023 vehicle. If a reveal is pushed back to the first quarter of next year, you're likely looking at 2024 models. And no, at this point there's no indication that Audi will send the new A4 Avant to North America.

Interested in more news on vehicles soon to debut? Check out our preview of Pebble Beach and Monterey Car Week in the Rambling About Cars podcast, available below.

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