In the Bulk Purchase Mode, you can allocate products both from the Future Inventory and On Hand Inventory.
Go to Purchase Orders > Add PO.
Click on the Inventory tab at top left of the display
In the Actions column, click on Allocate.
If you select a product From On Hand Inventory you must select the quantity to allocate and press the enter key. Once you do that, the line product will be added to an invoice. If no pending invoices are available that match the dates of the Prebook, the system will create a new invoice for that customer.
On the contrary, if you select a product from the Future Inventory, the next screen will be displayed. Once you enter the quantity to allocate, the line product from future inventory will be allocated to a Prebook.