multiple order status on preorder

Ideally we would like to give the OPTION to the customer to decide weather they want to:

a) pay once for the shipping cost and wait for the whole order until we get the out of stock item back in stock --> This means that the whole order must be kept ON HOLD in the warehouse. Not only the preorder item.

b) pay 2 times for the shipping cost and receive first the orders in stock and then get a 2nd order with just the item oos. --> this means that we will receive double shipping payment from the customer & that shopify needs to keep ONLY the PRE ORDER item in ON HOLD.