Normally when it says that on the website it means there are some stores that have it in stock so it can't be completely removed from the system until they are sold. But its very rare they do go back online.
I know they did this with the Zombie Army 4 CE preorder. Didn't preorder when it was first listed, then went to preorder it a week or so ago noticed it was no longer listed. Not sure if this means they sold out of preorders or the game has gotten delayed but I imagine it will show up again closer to release date.