So I’ve had my 21 Sierra 3.0 for 3 weeks. I’ve had the crank no start 2 times. Once while trying to remote start and the other when I went to push bottom to start. Both times cranked for 15 to 20 seconds with out starting and started on second attempt with no issue. I went in to the dealer today for a piece of trip that was popping off the window and mentioned it to them. He found the TSB and told me it wasn’t the Diesel engines with this issue it was the gas. But he did say I needed a software up date and the issue should be fixed. After reading this thread it’s obviously not just a gas engine issue.