GM pulled the VIN tracking system, we have to contact the support teams at either GMC's or Chevy's main site on the message us in the bottom left corner to see about a status update. I havent seen them change that, I have been waiting for mine as well, it was shipped about 2 weeks ago and its supposed to arrive on the 30th per GMC's support
Ordered my AT4 1500 Crew Cab with Standard Bed on 01/20/2021, got a call on 02/11/2021 from my dealership and told me that they no longer are doing the AT4 Premium Package no longer exists as the running boards are so backordered and that I have the max tow package on my truck and they have stopped all production on that packages because GM cannot get their hands on the semiconductor that runs the anti-sway system on the truck. My dealer told me that we can either keep it how it is and wait 6-9 months for the semiconductor or take off the running boards and the max tow package (Bringing the max tow from 9100lbs to 7100lbs). I chose to remove the max towing package and change the Premium package to Value Package and now my truck is being built this week, 3/8/2021. Hoping to see it soon!!