The customer should be then able to accept the order as a whole or accept parts individually (so separate accept buttons), in case they decide they do not need all of them after all. You could potentially put tick boxes next to each item preview and then the customer ticks the ones they need before clicking 'accept order'.
This could be done, but would get confusing, since the DropOff will contain all the parts. Also It's just one resubmission for the customer to do after he re-decides, so I think this is not a high priority.
From online managers: