@Harrison-and-Alex0 If you just update the current listing, all your reviews and ratings will show on the listing. You can say in the first line of your description that you have undertaken major renos and describe what they are. You could even add that the reviews dated before xx were given before you did all the renos.
If you create a new listing, your reviews will still show on your profile page, but not on the new listing and you'd be starting over with the ratings for that new listing.
You'd keep Superhost status, as far as I know, because that is attached to you as hosts, not pegged to the listing.
I'd go with the first option, myself.