I have found that items usually are sent much sooner than stated. Posted times are outside estimates. The order is not what you call "open." Be prepared to be patient or don't place the order.

Estimated shipping time does not mean the same as "open" order (I think I understand your meaning); Amazon usually lists the item "if available' if they don't know if the item is available or not, and this possibility is clearly stated.

On a couple of orders, I have received a message from Amazon that the item cannot be provided by the dates specified, and asking if I want the order to stand or be cancelled.