My order is one of the latest ones I think to be in this delivery window. My confirmation email is stamped 3:16 am - ordered 38mm Sport White Band. I was online when the site went live but had to put in 4 gift cards, so by the time the order was done it was a bit later.
I am choosing to believe that there is a good chance a large percentage of people (not necessarily all) in this window will get their watch on the 24th. I realize that might not happen though. I think the 2-week window is there as a cushion, and possibly there for certain configurations that were lower in supply (I'm looking at you Space Grey Black Sport Band).
Just my opinion...fingers crossed for everyone that we get them on the 24th or not long thereafter, hang in there everyone!