There is currently some kind of geomagnetic storm which is causing a lot of GPS tracks to be offset over the past few days. It's all over the running/cycling forums. Could be related, here's an example: https://old.reddit.com/r/Garmin/comments/vo17e2/the_magnetic...
NOAA doesn't list any meaningful geomagnetic storms right now: https://www.swpc.noaa.gov/communities/space-weather-enthusia... But that aside, I'd really hope that these cars are using professional WAAS-capable GPS receivers. Short of a major X-class flare which knocks out the WAAS geostationary satellites, the entire point of the system is to correct for these kinds of disturbances to the GPS signals.
[0] https://scitechdaily.com/auroras-incoming-giant-sunspot-has-...
[1] https://interestingengineering.com/a-huge-solar-eruption