Not sure what you are asking Jay. I've had dill go to seed in late Summer and that seed will self germinate the following spring, thus the term "Dill weed". Although I've cut dill after a frost I've never had it continue to mature or resume growth after a killing frost. Therefore if it has not progressed to forming a seed head going into winter it will simply die.

Dill is relatively fast growing. We have numerous requests for it (and corriander) potted which I have done but with a warning that the potted plant will probably look ugly within a few weeks. I assume that the heirloom variety you have is a tall type with a large seedhead so it may take longer to develop but just like for many other veggies in a high tunnel- if you want to harvest over winter it should be close to maturity going into the Fall.