Different companies have different plans. Arizona has had auto-driving trucks on freeways off and on for a couple years now as part of test programs. Always with a driver in the cab though.
A few years ago I would have though robo-convoys would be where things landed because three or four companies where working toward that. That's where the front truck has an operator and all the other trucks follow that leader driverlessly.
Now I feel like I have no idea where any of it is going. Step 1 in driverless should have always been to adopt an industry-wide mesh-network for all vehicles with level 3 (or higher) autonomy. If I'm on the road with (or inside of) an autonomous vehicle, I want it to be able get help from every other nearby car if its sensors suddenly die or start feeding it bad data. Especially after they've been on the road, poorly maintained by their owners, for a decade or more. If there are autonomous cars where will eventually be autonomous jalopies that drive like a drunk toddler because they sees lidar echos.