Reckon Hosted - Enable receiving deposits against Pending Invoices or Orders

Customers pay a deposit upon order.  The remainder is payable after the order is ready.  In order for the GST to be dated correctly, to receive a customer depost we have to create a special invoice for the deposit amount, then manually edit the pending invoice for the amount received.  The pending invoice is then converted to a tax invoice and issued when the final goods are available.  Being able to receipt the payment against the pending invoice or a sales order would make this much easier and less open to errors.