Beersinthegarden - I am delighted you were helped by my thread, I hope it all goes well. Please let everyone know the outcome.
Wingy - I too have heard buckfast can sometimes become defensive if run for too many generations. Using my own stock I can only rear more F3s or F4s. I have also heard many times how productive good buckfast bees are.
So maintaining productive stock and reducing the likelihood of developing defensiveness is my thinking behind re-queening.
I don't think my tetchy hive is of particular concern. They have never stung me, they don't follow. I can use the lawn mower right next the hive and they are not bothered.
But as soon as I crack the lid, I am usually greeted by a little sortie that want to investigate my face. There have been a few times mid inspection when in the blink of an eye, 50% of the box are suddenly in the air. Its nothing a puff of smoke cant handle, but my f2s have never done that.
My other F3 is still in a single brood, their numbers are lower so its hard to gauge their defensiveness.
I am curious to run at least one of the f3s next season, just to see how they do. I would like to see how they compare to the f2s in terms of productiveness.
I am also thinking if I do re-queen one of the f3s, then I will be able to use brood as others have suggested to raise more f2s should I need them.
If anyone else has bucks, do you get these problems and do you also have to periodically bring in new queens?