Rarely do I need to use studded tyres here (we salt a lot, and winters are getting milder), but it is generally good to have an idea where there might be ice when it's hovering around freezing: Overpasses (because it's a bridge), in the shade, and any place where there might not be salted that well: Roundabouts and tight turns where the salter end will be pivoted out in the road when it turned, and did I mention the shade?
I also allow my bike to take the brunt depending on the type of fall. Fast moving, I try to roll out of it.
But anyway, when it's around freezing, especially in the morning there are places where the ground will still be cold enough to not have thawed, and there are in general places where it is aways dicy if it's freezing or close to.
If you do hit a patch of ice, do not turn, but do move your weight towards the rear.