We have two boxes that both successfully hosted three broods. We cleaned out the boxes and looked forward to spring. Now (last week of Oct) they appear to be building new nests and somewhat arguing over the boxes. We are in northern Indiana and anticipated the birds wintering a bit further south than here. Will they winter this far north? We are not sure if we should continue to support them or take action to force their southern flight. I read an entry last week that suggested putting tape on the box vents to help them maintain their winter box temperatures.