From the FAQs on CW's website if you read the 'NB:'.
"What does ‘preorder’ mean?
Preorder means that this watch is not yet ready and we’re waiting for its first delivery (or we’re temporarily out of stock). The preorder date is the date we expect it to be ready to ship to customers.
NB: If you order a preorder watch, we will not charge credit card payments until it is ready to be shipped. For payments by PayPal, the funds will be taken immediately."