In all the chats I've had with apple (chat), they say it typically takes about 24-48 hours for an order to change from "Preparing for Shipment" to "Shipped".. and stress waiting for Apple to email you with your tracking number and definite delivery date.
Some people have been getting their watches earlier than the window of delivery (for you, June 25 - July 2), but it really depends on the model/size/band/colour etc of what you ordered.
I can't tell you when it will ship, just to wait for apple to send you a confirmation email of your tracking number.