the life of landing, taxi lights can be just hours if they are not mounted correctly and vibrate, due to missing mounting strips and are loose in the housing. hitting birds breaks them as well.
to change can be as little as 10 minutes, it mounted on the nose leg gear and can be reached with out steps, if mounted inside the wing root and need a platform or steps to get access and an access panel taken down with worn out screw heads then time can be 40 minutes, and a trail to do it in a transit turnaround time.