Beamng vehicles are structured into folders, with one for each vehicle: for example vehicles/scintilla, vehicles/covet, vehicles/coupe (200bx), etc. Each of these folders get loaded when you spawn one of these vehicles. There's an additional folder, called vehicles/common, that loads when you start up the game: it contains stuff that's used on multiple vehicles, and helps to avoid duplicates
It may not necessarily be the case, the rule was that all wheels go in the common folder. I believe only the Aurata wheels are not in common folder (despite being standard wheels – @devs, please, all you need to do is to move two folders and a few textures).
I heard that the Aurata wheels aren’t in Common because of some issues regarding them, not sure what that’s about.
Well, yes, it was me who asked about it , but I still don't buy it. I've just tried them on a Covet* and apart from not fitting the arches because they're a bit too big, they seem to work just fine. And, uh, you can put 28" rims on a Piccolina too, so I am even more confused about it. But I digress. Spoiler: * * Because all you need to make them common is to move wheels and tires folders from utv folder to common and the main.materials file (remove other materials to make it cleaner). They even come with separate .dae files, so you don't have to separate them either.
Back to speculation: Maybe they are working on a new hatchback kind of thing. I just read the update blog where they showed the new blender tool. Maybe that shell of a car was some kind of a teaser? Just thinkin...
It's the Jbeam for the ETK 800 wagon. Nothing really all that important about that. Besides, I dunno why there'd be another modern hatchback added to the game right now when we already have the FCV for that. Not saying there's no chance for another modern hatchback, but the devs have been flying through all the categories they didn't cover before (like a minivan, a UTV, an amphibious ATV, a modern supercar, and a modern American sedan, among others) in the past 2-3 years, and I doubt they'd want to take 6-8 months to make a vehicle for a category that's already been filled.
It could still happen, but it's unlikely - most teasers are posted before 6 PM German time, and it's currently 6:19 PM over there.
is there even an update in the works what if they are taking a break for a bit that could explain the message saying there could be slower mod releases
There's been an update just about every single December since 2015 - I don't see why there wouldn't be one this year. Only in 2017 did the final update of the year not happen in December - and 0.11 happened around Thanksgiving of that year. (Sometimes, there's even been two major updates, like with 0.5/5.1 in 2015, 0.18/18.3 in 2019, and 0.24/24.1 in 2021.)