It might begin very soon

A trucker drives his rig to either a shipping point or the delivery point. He has to stop at the security gate out front for farther information or get out of his rig, once he is in the yard, and find a receiving/shipping person and get a dock number and a load/unload time. Sometimes the driver is told to leave and come back at another time.
I doubt the warehouse/customer is going to spend millions of bucks setting up a system to handle drivers free trucks.

I can see how a intermodel shipping yard like UP or BNSF could use driver less pony trucks to move containers around in those huge yards.