Thanks very much for your comments D Coates, I've had them in the #4 position all summer. I will move them as per your experience seeing that they are full of honey and there was a very few brood on one frame too. Question, do you have them in every brood chamber or just one? I'm obviously running with double brood chambers and will go into the winter that way. I keep a drone frame in both my brood chambers and pull them every 3wks as well. This being my first season, and only got my bees in late June, I've only pulled one set of frames ... I did check the larva after being frozen and couldn't find a mite ... so that is good. I'm doing a mite count now so that will tell us what our levels are too.
Thanks again.