The Hot Pepper

Leave them alone and see what happens.

I agree, let them ripen on the plant as long as possible until it is going to freeze. When it is going to freeze, I would either bring the plants indoors in containers to finish ripening, or just harvest them and leave the peppers on the counter to finish ripening at room temperature, and hope for the best. Sometimes it works. Worst case, green peppers are still perfectly usable.

cut the plant at the stalk and hang it upside down to get those pesky few to try and ripen.