I think they might have some issues with wet coal in the wet season too, because most of these coal are stored in the open and in the dry season the coal is dry and more efficient. Wet coal being less efficient will increase electricity prices in the wet season, so these miners might be going north to operate in an environment where there are no seasonal influences in the electricity prices.
It is all about efficiency, because cheaper electricity = more profits. ^smile^
Its just a common sense to think off on a certain company or group on this way.As long on where the business would be profitable they will surely make changes later on. They shut because they saw that they aren't making money and would need to move to another place.