People should contact their bank or credit card company when they ordered at the start of the pre-order window, as there's been more than 30 days between the pre-authorization and the now charging of their card for the watch.
Many cards / banks automatically decline these transactions (and don't notify their customers of having done so) as part of their fraud protection.
By giving your bank / CC company the "heads up" you should keep your payments from being declined, so you don't risk receiving your order in a timely manner.
Now, if your payment has been declined
This bit from fireguy286:
Call the number on your card and get the payment opened again. In some cases your whole card may be frozen until you do, not just that Apple purchase.
You can either call Apple back after that and have them reauthorize, or on your order status page there will be banner with red text above your order with a button to update payment options. The lightbox popup from there will let you either reauthorize the card on the order or enter a new method. When that's done it will tell you it's successful (hopefully...) and you'll get a confirmation email. That's it.
Many cards / banks automatically decline these transactions (and don't notify their customers of having done so) as part of their fraud protection.
By giving your bank / CC company the "heads up" you should keep your payments from being declined, so you don't risk receiving your order in a timely manner.
Now, if your payment has been declined
This bit from fireguy286:
Call the number on your card and get the payment opened again. In some cases your whole card may be frozen until you do, not just that Apple purchase.
You can either call Apple back after that and have them reauthorize, or on your order status page there will be banner with red text above your order with a button to update payment options. The lightbox popup from there will let you either reauthorize the card on the order or enter a new method. When that's done it will tell you it's successful (hopefully...) and you'll get a confirmation email. That's it.