On the official forums for Strauss & Howe generational theory, the community uses "Gen Y" to refer to late-wave Gen X-ers and early-wave Millennials who have so

On the official forums for Strauss & Howe generational theory, the community uses "Gen Y" to refer to late-wave Gen X-ers and early-wave Millennials who have some of the social characteristics of both generations due to being on the cusp. The exact years are nebulously-defined (cusps typically are, since they're unofficial extensions of the theory), but I've seen it defined as wide as people born 1977-1988. Mid-80s are almost universally accepted as part of the cusp, but how early or how late it extends beyond that seems to vary.