Orders placed via PayPal will be charged at the time of placing the order, regardless of whether the items are on pre-order or not.
For orders placed via credit or debit cards, the order total is pre-authorized in order to confirm and secure your items. This amount is simply ring-fenced by your bank and is not sent to them. This is reflected in your account by your bank within 3-5 working days. Your card issuer dictates the time it takes for this to return to you; they have no control over this.
When they come to process the order for dispatch, they then fully debit this amount from your account. Processing orders may commence the week before the dispatch date.
Pre-ordered items are typically dispatched the day before the release date of the item. Delivery of the pre-ordered items would then fall in line with the delivery method selected at checkout.