Orders are unable to be edited after they have been submitted. This is a function of how courier APIs work when sending orders to them in that once sent, you must cancel the order and then rebook with the changes required.
The way to 'edit' an order is to collect the changes required to be made, cancel the original and resubmit with the new requirements.
We strongly recommend you do not allow editing of orders within a certain time to pick up or urgent orders whatsoever. If a courier is booked and a driver assigned, the merchants will be liable to cancellation fees - it may well work out cheaper to pay wait time fees than cancel and rebook. In addition, during peak times, couriers take longer to assign drivers so canceling and rebooking a driver may risk delays.