Tbh I don't think it wasn't done early out of goodness of the heart. I'm sure you remember strikes at substations around Kiev before winter. Frankly I suspect it was for the same reason that railways, bridges and resource extraction infrastructure (such as ammonia pipelines) weren't targeted - Russian capital wanted them. Now it's clear western "partners" would rather it all burns, so they go ahead
Tbh I don't think it wasn't done early out of goodness of the heart. I'm sure you remember strikes at substations around Kiev before winter. Frankly I suspect it was for the same reason that railways, bridges and resource extraction infrastructure (such as ammonia pipelines) weren't targeted - Russian capital wanted them. Now it's clear western "partners" would rather it all burns, so they go ahead