Had the same thing happen to my truck. For some reason the update didn't download and install correctly. All the same symptoms. Brought to the dealer today, and they still have my truck. I will keep you updated. They cant get it into neutral.
New 2023 Silverado Bison Rock Sliders For Sale, I had to replace them with running boards, was too difficult for the wife to get in the truck. Located in Ontario, Ca. asking $700. No scratches or dings.