Self-driving fleets of cars might be sharing the streets with human drivers sooner than many thought; Reuters reports that GM will field “thousands” of self-driving electric test vehicles, primarily based on the Chevrolet Bolt platform, starting in 2018. The fleets will primarily be used with partner Lyft for on-demand ride-hailing service, according to the report.

That’s a lot sooner than the proposed 2020 date Ford and others have been targeting for large-scale deployment of autonomous vehicle fleets in similar ride-sharing functions. The report does call this specifically a launch of “test fleets,” so these vehicles will still likely not be positioned as a commercial debut of a service, but it sounds like we could still see them in active service with customers, since Lyft is said to be planning to operate them in a test capacity in multiple states among its ride-sharing service fleet.

GM has said previously, and reiterated when contacted by Reuters, that it intends to start piloting its autonomous vehicle tech in ride-sharing services “sooner than you might think.” The company has also been sharing regular updates from GM-owned Cruise, which is actively testing autonomous Bolt EVs driving city streets in San Francisco, as well as in Arizona, with plans to expand to Michigan roads soon.

In the course of testing its Cruise fleet, GM has made use of a smartphone app that allows a user to choose a beginning and end point for the trip, and it’s very likely we’ll see similar technology used in any consumer-facing trials at a larger scale. GM and Lyft also previously discussed (in May 2016) plans to begin testing self-driving taxi service on public roads “within a year.”

Lyft rival Uber also recently announced that Daimler would be the first automaker joining its so-called SDV, or self-driving vehicle platform, which is open to all OEMs and will allow them to operate fleets of their own autonomous cars on Uber’s network for ride-hailing services. The tie-up between Lyft and GM has seemed a more exclusive arrangement, and it looks likely to remain that way at least through this test period, if this report is accurate.