Yes you might be right Kevin, I might let the girls keep building themselves up and will buy a queen and split them in spring. I have noticed a large reduction in pollen coming into the hives over the last month.
I wouldn't bother with buying queens, just split them and let the bees sort it out; they know what to do. Leave them until Spring, then keep an eye on them. They'll start building queen cells, then you have to jump and get to splitting.