OTA Software Download
WARNING: This page is about a different car, the 2020 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.
In order for an OTA update to be pushed to a vehicle, the vehicle must be parked for the entire download process. There is not a notification to the driver that the software update is being downloaded to the vehicle. Battery SOC and OAT values are not checked before a download. These checks are only performed once the software update is downloaded and ready to be installed.
The OTA software download can occur in increments. So if the vehicle is driven during the download process, the download will be paused until the vehicle is parked and download conditions are met again.