Harvested plants can come inside for rejuvenation under continuous light or are left outside in Summer to rejuvenate in the natural long days. It will take 7-14 days to see signs of new growth when regenerating a plant. As stated before, and in contrast to normal growth patterns, lower branches will be the first to sprout new vegetative growth.
Allow the plant to grow a little vegetatively, then take outside again to reflower. Or keep inside for vegetative cuttings. You now have two or three generations of plants growing, and will need more space outside. But you will now be harvesting twice as often. As often as every 30 days, since you have new clones or seedlings growing, vegetative plants ready to flower, and regenerated plants flowering too.
Regenerating indoors can create problems if your plants are infected with pests. It may be best to have a separate area indoors that will not allow your plants to infect the main indoor area. An alternative to regenerating indoors is to regenerate outdoors in the Summer. Just take a harvest in June, then allow the plant to regenerate by leaving some lower buds on the plant, and leaving the middle 1/3rd of the plant's leaves at harvest. Feed it nitrogen, and make sure it gets lots of sun. It will regenerate all Summer and be quite large by Fall, when it will start to flower again naturally.
Good luck !