This is not about lane control, it is to attempt to prevent in Australia, left/next exits on some Roundabouts when a dedicated exit is missed.

The are RABs that you can not take the first exit on, you had to have taken an exit lane before the RAB.

It would be useful to be able to restrict these particular exit choices when required. A JB would be drawn to cover the area and be allowed to restrict that particular A-B.

Thanks.