Justin: definitely call A/G. Light timing is controlled in the base of your A/G. Mine are old A/G "Classics" and I don't have a 20/4 schedule. If you a newer model and you didn't program it wrong there may be something wrong with the unit.
You can also get a remote timer from almost any hardware store this time of year, disconnect the lamp cord from the base, plug it into a figure eight cord and then control the lights from the timer.
How old are your lamps? A/G recommends changing lamps every six months. I've heard of them getting dimmer but not going out on their own. HSA