ball pythons do not require a light cycle, and the benefits of offering a light cycle are still debated.
you might need to up the wattage of the bulb due to the height of the enclosure. in my 20gal (long) i run a 100 W CHE on a rheostat which keep the ambient temp at ~80° F. honestly i'd ditch the bulb and get a CHE that you can run all the time which will also allow you to keep the thermostat setting for the UTH consistant. no temp drops, no adjusting, just 24/7 ball python comfort.
for bulb regulation you can use either a thermostat, or a rheostat (lamp dimmer). i use rheostats for both my lamps and they work well and are also more affordable. it takes some time to learn the dial but you'll get the hang of it within an hour or two.