Adding to an existing reservation

We have divers confirmed and here diving with us. They want to add dives so we enter it onto the invoice. The dives dont get pushed to the calendar because they were not confirmed by the diver. I think this could cause us some trouble. I think when we have an already confirmed reservation, and we add dives to the roster, those should auto-confirm and immediately push to the calendar. I can easily see myself or my staff not seeing it didnt get reserved and then we forget the divers for that added dives that never made it to the calendar. Currently I forced it with the “reserve” button but again I can see myself forgetting to click that button.