olsen point
the saturation point(s) for bit characters and other supporting story elements (in the development of a narrative body, shared universe, or microgenre) at which those characters or story elements can support the weight of their own separate (if parallel) narratives
Superman's pal, Jimmy Olsen, hit his olsen point when, due to the popularity of actor Jack Larson's portrayal of Jimmy, the character was given his own regular title in the lead role.