When do you remove your winter protection from rhodies?

I got my protection on late, and I never did protect Cherry Cheesecake. I did move CC to right up against the house in a spot nearly completely protected from wind, but I'll bet she would have loved a burlap dress anyway. We'll see how she does. But, back to topic, when do you remove the protection? I'd like to get some sun to the leaves. We've had warm temps in the 50s which then swing to the 20s.