I'm trying to purchase a De Gea jersey, but it says it's available to preorder. Does this mean it's not been released for the public to purchase yet, or does it mean it's out of stock and you're preordering for the next batch? Also, is there any way to tell when it'll ship out then?

Sorry for all the questions, I've never placed an order through store.manutd before and it's pretty badly laid out.