mapkit overlay is readonly, how to remove them or refresh the entire mapview?
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The solution online to remove overlays and refresh mapview do absolutely nothing. I am sure I have all the delegate set and everything hooked up. Looking for creative ways to solve this problem. What I intend to do is to show "directions" ( the polyline) to new destination coordinates only, but not the old destination. But once they are added, they cannot be removed it seems.....

     [mapView removeOverlays:[mapView overlays]];

and 

     [mapView setNeedsDisplay];

both does nothing!
