Orders cannot be split after your order has been placed. You're welcome to remove items from your order and place a new, second order for those items. However, our system automatically combines "Ship Now" orders if they are placed within a few hours of each other, or if they have the same shipping method and their items come into stock at the same time.
Because of this, we recommend avoiding the possibility altogether by using the Private Warehouse handling method. You can easily change your order's handling method to "Private Warehouse" from the My Account area before it has been billed.
No changes can be made to any order once its shipping cost is paid and it has entered shipping processing. Please be certain to make any necessary adjustments to your order before your order has been paid.