It will probably take them 2 days to sort through the order, and probably a month or so before they're done everything else and they can get around to checking it.
Now this is pure speculation, but I think they delay it for two reasons. One is to see what you do about it. Two is if theres any dangerous goods in it, you won't have them for the time that you require them. Because you know, terrorists don't plan ahead when importing dangerous goods or anything.