following on from the “going car-less” thread, if both drivers in the family have good no-claims discounts, and you decide to get rid of one of the cars, and therefore one of the insurance policies, do you keep your NCD topping up when you’re a named driver on another policy?

Example:
I have a car, my own insurance & mrs_d is a named driver on my policy
Mrs_d also has a car, her own insurance and I’m a named driver on her policy

If we get rid of one of the cars, we only need one policy, correct?
I have 12 years NCD and my commute is a 60 mile round trip; she has 9 years NCD & walks to work.

If I sell my car & cancel my policy, and continue to drive her car on her policy, would I continue building up my NCD?

Or would I be better changing my policy so that I’m the main driver on the remaining car & she’s a named driver on that policy, while she can cancel her policy & save the monthly premium?