Chiefman, Its a piece of string question you are posing. What are your flows, how reliable are they, what is the weather likely to do, how often can you feed them, is there plenty of pollen, etc. No-one will likely give you a date as this is dependent on the area and seasonal conditions which only you can answer. If you really want to make a split from this queen then I would do it sooner rather than later but only you can make the final call.