The company's website suggests that you can change the position of the sun, presumably there's nothing preventing you from modifying it on a timer or slider.
Actually, the light is set at a certain angle and can't be changed [0]. They let you choose between different angles – 60º, 45º, and 30º (mounted on the wall). They say that they are working on allowing for light adjustment in the future [1].
(Not your fault though - their website is pretty sparse on information.)