Which side for their sand bath?

[pac]

I get sun in the summer and snow in the winter.
I'm guessing I can keep the food and water in the open side of my hutch year round. The side with hardware cloth everywhere but the roof. Unless something happens where I get snow accumulation in the open side... in which case I can staple some plastic up to block it. And then it won't be so open. But it would be nice if the birds did at least some of their poopin' where it can fall into a litter pan.

But which side for their sandbox?

I've read (mostly here) not to put it in direct sunlight.
That it needs cleaned regularly.
That you often find eggs in the sand. (Does this mean they prefer hanging out in the sand even if they aren't bathing?)
And to keep it in one spot. I'm not understanding that, but I read it here.

So for a year round place for their sandbox, maybe put it in the enclosed side?
Maybe it's not a good idea to make it too crowded on one side or the other with the sand, food, and water.
Maybe if the sand is in the enclosed side it will give me extra time before the eggs freeze.

What do you cold weather quail keepers do?