I agree that it was poorly done. I think they were supposed to be remastered but I didn't really notice a difference.
My job involves ordering things from print shops/manufacturers and you have to plan things a long time in advance. It can take months to get the products made, if there isn't a long line ahead of you. Then it takes time to get it out to retail stores...plan advertising etc. I would say at least 4-6 months to be on the safe side, but I don't work for a record label so obviously that's just a somewhat educated guess. (Though I've created and ordered printed products in under a month before - I guess it's possible.)
If I remember right I think they were doing those cardboard covers at the time - I hated those!