The Etis date is a place holder until it is built. If your Window Sticker link works, view it and look at the numbers at the top where it says the word BLEND. If you build date is 12/15 it would say 1215.
Hope this helps
Can you see any other information, like an EDD? I have no build week but it does show a delivery date. I think it might mean my build week is 12/8 :shrug: