Merging orders in one backorder list
We are producer of the products we sell to shops and distributors. This means we sell products which will be delivered a year or more later when the production is finished. When a buyer orders a product which is not in stock it will be added to the backorder. In our current system (Unit 4 Multivers) every new order is added to (merged with) the original order number of this particular buyer. This is implemented this way because otherwise a buyer might have a hundred separate orders, which are backordered. Unworkable when new stock is delivered. You end up with dozens of packing lists and invoices, while just one is needed.
When new products are delivered and stock is updated, the original order is split into an order with the backordered items, which are still not in stock, and an order of products which are in stock now. Only then an invoice is send out for this order after the backorder has been updated. Usualy we only ship when the combined value is over 250 EUR. We want to generate an invoice manually. Sometimes we need to calculate the shipping before making an invoice.
Is the single shop API suitable to implement this system? Our customers should also be able to log in and view their complete backorder list, so they can make decisions on what to buy.