Rumours of an upcoming BMW X8 have been around since 2017 when BMW’s then head of development, Klaus Fröhlich, said in an interview that the automaker's considering the model.

Then last year, the first sighting of the sports activity vehicle to slot above the BMW X7 happened, basically confirming that the biggest of the X models is indeed coming. However, Bavaria hasn't confirmed its arrival yet nor has it confirmed that it will indeed be called the X8.

But if you have any doubt, here's another sighting of a supposed prototype caught by our spies – and it's flaunting its unusual tailpipe layout again just like we've seen last month.

Gallery: BMW X8 Spied Flaunting Unusual Tailpipe Layout

Expected to become the new flagship BMW SUV, the prototype here was spotted at the Nurburgring. Despite the bevy of claddings and concealment to hide its design, there are several cues here that tell us that this isn't the facelifted version of the X7 that we saw recently.

The front looks flatter than the X7, while the bonnet has prominent lines and the lower intakes have been reshaped. The headlights are positioned lower than the current X7, though this aligns the alleged X8 with the upcoming X7 refresh in terms of headlamp design – albeit the X8 isn't showing any sign of a split-headlight design.

And yes, the massive kidneys found on the X7 will likely appear on the X8 as well, given the spy shots that you see here.

While you'd expect the X8 to have a coupe-like roofline just like the 8 Series, the spy shots are telling us otherwise – but we're still expecting surprises, so there's that.

As for the powertrain, the prototype here is carrying an electrified setup based on the stickers, so it's likely the rumoured high-performance plug-in hybrid X8.

Then again, nothing's certain at this point, at least not until BMW puts out an official word about the upcoming model. For now, all we can do is wait for more prototype sightings.