In the wild the seasons are what dictate when "breeding season" begins. For most this is because of change in temperature and/or precipitation. With that said some snakes breed year round (African house snakes for example). Some snakes only breed once a year but do not require any kind of environmental ques. As long as the male and female are healthy and of proper age all you need to do is put them together.
Many ball python breeders are successful without a temp drop prior to breeding season. Some still do. Some breed at different times of the year. We paired ours last Nov and the female waited to ovulate until late July (eggs in the incubator right now).
Bottom line, you can do what ever you want but they will go when they are ready to go.