Yes and no... in anybody's case, it depends on when you pre-ordered.
How this works is really about the quantity of watches in any given size/style/color Best Buy will get from Apple and in turn, this quantity is limited. It then boils down to demand. In this case, AW4, demand is pretty high at this point and so any watches they may have, are gone at this point and now it's into a back-order situation.
Anything you order now goes into a queue and when supply becomes available, they will ship it to you. Currently, supply and demand is to a point where you're looking at early to mid October for delivery on the most popular styles/colors.
Watches that are on the less popular side may have a chance at late September, early October.
The only chance you really have of getting a watch on release day is to submit a pre-order within hours (the earlier the better) it is available for pre-order (12am Pacific/3am Eastern on Sept. 14th for the AW4). That's how you come the closest to guaranteeing yourself a watch on release day.
The second option right now is going to your local Best Buy at or before opening time on release day (tomorrow) to have a chance at watches that they may receive for sale on release day... And i'd venture to guess, if you really want one, you better get there a fair amount earlier than the store opens... 30-60 minutes, or more. Depending on your area and the population your store serves. In larger cities, you are likely to have more individuals show up before store opening and in smaller towns and cities.
I hope this helps. :) Good luck to you.