[gremlin]

I would get it roughly dug as soon as you can so it drains a bit.

I agree with everything New Shoot except if you open it up now, it wont drain but any rain and snow we get will soak deep into the soil through the cracks and make the soil even wetter. I don't even cover my plot over winter because I have found the plastic traps the water in the soil and prevents it evaporating when the sun does appear. I leave it undug over the winter and the puddles stay on the surface, but don't soak in. My plot is solid clay 12" down

As soon as we get dry weather, a bit of sun or a drying wind,  I rough dig my plot to let the air in and the moisture evaporate.  Dry soil warms up so much faster.  Wet soil remains cold for weeks longer. 

[Beekissed]

Since you are into permaculture, you might find this film interesting as it applies to amending clay based soils in a more permanent and sustainable manner:  http://www.backtoedenfilm.com/