I found the following information about eventually downloading your prepurchased content:
If you've enabled iTunes to automatically download prepurchased content, then your pre-order content may already be downloaded to your library. If not, simply click the download link provided within your email notification, and your pre-order content will begin to download. Alternatively you can use the "Check for Available Downloads" feature in iTunes on your computer by choosing Store > Check for Available Downloads to begin downloading your pre-order.
Also, if you want to view, cancel, or see the expected release dates for your pending pre-orders, you would follow these steps:
- Choose Store > View My Appie ID, then click Manage Pre-orders, which located in the Settings section at the bottom of the Account Information screen in iTunes on your computer.
- From the Mange Pre-orders screen, click the Cancel button to the right of the pre-order item you would like to cancel. You'll be asked to confirm your pre-order cancellation.
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