We haven't had any accidents since snow started. Becca is confused about how to potty in deep snow though. I have made some paths in her favorite spot. It takes her twice the amount of time to decide where to go. Do your dogs have a "go potty" command? I'll tell Becca to "go potty". She will start circling in the snow, but it takes up to 10 min. to find the perfect spot.
It is funny because last night it took her forever to choose a spot. This morning with a few more inches of snow, no problem. I'm not sure how helpful this was, but I feel your frustration.