I have a similar issue. I have some scratches from a parking accident. I have spoken to motability as I also need the GCB . I was informed that they are told during your MOT if the car passes the GCB. So after your MOT ring them and ask. If they say no. Then phone RSA and get it sorted . If your over 25 will cost you £100 but if it protects your GCB it has to be worth it