I see one of two scenarios here.
1. they took money knowing full well they could never meet a ship date they promised to customers.
2. they have no clue as to how a manufacturing process actually works, or the time windows needed.
Both are plausible, sadly.
There's a third option I'm wondering about. The product page shows two interesting cards. One shows "Tensor the Crazy Wizard" and the other shows a "Gygaxian Ring". It is possible that they received legal threats from WotC or Gail Gygax (or both) for using these names, and need to do reprints as a result. I suppose we'll know when the game finally ships and see if either of these cards make it to the final product.
As always... Hi, Michael @TSR-Hobbies! We're here asking questions about TSR, and are open to discussion any time you want to talk.