You open them when you get them. And I got this Kmart Case well after the actual event.
No worries though, because ordering cases seems to be the best way to go these days. It it is the only option if you don't live near a Kmart, which is becoming the more likely scenario these days with so many Kmarts closing.
But even if a Kmart is close, ordering a case makes sense. You get a 36-count case with the exclusives and first-to-markets guaranteed to be inside. That qualifies you for at least one mail in. Go buy four more at Kmart and get two if you want. Donate the models you don't want to the local hospital. They will have plenty of use for them.
And who knows? Maybe you pull a Super or something else cool, without a creepy dude over your shoulder trying to see what you pulled. Win win. Except for that creepy dude.
Anyway, my Kmart B Case arrived, and here is the unboxing. (And yeah, I will post a case report later as well.)