I am on pc steam, so still playing on the early access build, currently doing the "Trough fire and flames" scenario on the Cajon Pass route and I have been noticing the vehicles that are driving on the highway, are popping in and out of existence even when players are within their expected render distance. I have posted a video below with evidence of this issue, no specific recreation instructions, just play the route and notice.
I noted this in another thread. I have also seen vehicles floating above the surface at certain locations and one did an abrupt U-turn to head back in the opposite direction on the wrong side of the road. Sounds like the car spawner placement needs revisiting - not a game breaking bug, but it doesn't help with immersion.