Announced on Google’s Pixel support thread, the update is described as a “Fix for GPS location failure under certain conditions.”
Google says the rollout for the update started August 4th, and will continue over next week, depending on carrier networks. Additionally, “Users will receive a notification once the OTA becomes available for their device,” reads the support thread. The GPS issue likely does not affect older Pixel devices, and hence, those devices were left out of the update.
Further, Google took the opportunity to address the delayed August security patch, stating that it will “begin rollout in the coming weeks.” The patch, whenever it releases, will address 40 security issues ranging from moderate to high severity across the kernel, modem, and camera.