Hello YR,
ROC - Reassignment of Confirmation is very much useful in the business context where you'd like to keep the system updated with the correct confirmations specially in a FMG scenarios.
Imagine a situation like this. You have a stock of 100 Pcs. There is a low priority order that has been entered at 10:00 AM and it took all the 100 PCs of stock. Now, there is another high priority document that came in at 03:00 PM. In this case, ROC gets triggered and takes the stock away from the lower priority document. If your business process is such that you can wait till the next day for the correct confirmations, then you don't need ROC and overnight BOP processes are enough to handle this.
And, yes ROC does real time update to both the sales orders ( donor and reciever ) as there is a small BOP that triggers in the background to exchange the confirmations. The Sales order in ECC system gets updated with the help of a queue.
Hope this helps
Babu Kilari