I ordered a 12.9 inch 256 GB wifi model and got this:
Pretty sure this means I'm getting one from the first batch, which was my goal.
EDIT: I got the empty bag issue too, so I immediately switched to the Apple Store app on my phone and was able to order it pretty fast. I think before most people on a computer could because of the empty bag thing.
12.9, Silver, 256GB, Wifi, May 21 - May 28 (Czech Republic). Bit of a pain to order, every time I tried to pay it removed the item from the bag and I had to try again, about 6 attempts before it worked.