Doesn’t a drink driving conviction stay on your licence for 10.years? Yes valid for 10 years and stays on for a further year. Not sure about insurance companies requirements for notification. Going on points being 3,4 and 5 i’d suspect a longer period of notification to insurance. So i’d expect them to expect you to declare it for at least 12 years based other convictions. I supposed they could ask for longer for serious ones like that.
Edit just read it again they are considered spent after 5 years so cannot be used to make policy decisions apparently.