This is my timeline.
1. Reserved Sierra 1500 AT4 through GMC website for $100 on 1/7/22.
2. Dealer contacted me on 1/27/22 to place order. Total was $68,470 pretty much fully loaded.
3. Got email from GMC on 2/4/22 with the customer order guide which was late since I had already placed my order.
4. Waiting for whatever the next step is...
Something I did not know is that the AT4 only comes with Duramax or 6.2 L engines. I ordered the 6.2L. I could upload the "receipt" if you'd like.