GM already has the second-biggest test fleet, with 50 or so autonomous Bolts currently on the roads in San Francisco, Detroit and Scottsdale. Alphabet's Waymo, for comparison, has about 80 of its own in various cities. A larger fleet means the company can gather larger quantities of data in more diverse driving situations even faster, thereby accelerating the software's training and making it easier to validate the system in the real world.

Additionally, IEEE Spectrum reports that the next generation of autonomous Bolts will get a hardware upgrade in the form of two new radar systems. According to some FCC paperwork, GM is seeking approval to test short-range radar systems from Japanese company Alps Electric and automotive supplier Bosch is also seeking to test a new mid-range radar system in a fleet of "highly automated driving" vehicles that matches GM's footprint. Assuming GM, Alps and Bosch all get the FCC approval they're seeking, the new fleet of Chevy Bolts could start hitting the road as early as May 1st.