Some details
The account over at Slashdot has a few more details. Apparently the original source was The Verge Two quotes from The Verge article:
The company is filing the recall with the National Highway Traffic Safety Administration (NHTSA) after completing a software update to 672 vehicles — the total number of driverless-capable vehicles in Waymo’s fleet. The update corrects an error in the software that “assigned a low damage score” to the telephone pole, and updates its map to account for the hard road edge in the alleyway that was not previously included. ...
... an unoccupied Waymo vehicle was driving to a passenger pickup location through an alley that was lined on both sides by wooden telephone poles. The poles were not up on a curb but level with the road and surrounded with longitudinal yellow striping to define the viable path for vehicles. As it was pulling over, the Waymo vehicle struck one of the poles at a speed of 8mph, sustaining some damage, the company said.