** It almost seems like the water is coming up the drain and freezing inside the freezer around the hole. But that doesn't seem possible. **
No it doesn't.
** What is tha that drain hole for? **
To drain defrost water out of the refrigerator cabinet before it can freeze. Automatic defrosting will occur every 6-8+ hours depending on the control system of the appliance.
** any ideas what is happening here? **
I can only think that drain line is either plugged or partially obstructed and not allowing defrost water to drain through it properly. After a defrost cycle when the appliance starts cooling again, any residual water freezes totally blocking the drain hole. It is a common occurrence.
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