IMO when to harvest has much more to do with the state of the trichs than the temperature. Weather can be totally random, your first frost could come weeks earlier than you're expecting, making your harvest too early if you harvest based on the frost schedule, or you could hit a warm spell and the trichs could degrade too far while your waiting for that silly frost to come already. If it comes early I recommend (if this is possible in your situation) covering the plants with as light a plastic garbage bag as you can find so you can keep the plants going a few more weeks. Good luck!
