How to store no yeast dough
Dough grows moldy in the fridge after several days. While it might keep 40 hours, it's more secure in the freezer. 

Depending on what you want to make with it, it might be better to work it from cold or from warm. If it is better from cold (e.g. pie crust, pierogi should behave similarly), freezer is perfect. If it is better from warm, you'll have to plan for sufficient time to unfreeze and let it warm up. In this case, the fridge might be better despite some mold risk.