Yes, it is unlimited, which means there are no limits to the number of requests or revisions. However, remember that we are still human, and it takes time to complete each request.
So, if you do happen to put in 10 requests today, it doesn't necessarily mean that we will be able to complete them all right away.
But it does, however, mean that we will complete all of them in a timely manner, and there will be no fluctuation in cost.