What is the longest you have been a member of the same young, mixed-gender friend group or organization?

In a long-term mixed-gender group, people know each other for a long time and (I suspect) are more likely to judge each other based on character rather than quick-fix social skills.

For instance, if at age 23, you still live in the town you grew up, and you still have the same mixed-gender friend group from when you were in 9th grade, that might count.

If you had a mixed-gender group of friends in college who you still see once or twice a year due to frequent reunions, that could count.

Do RP techniques work equally well in those long-term groups, for women you have known for many years? Or is BP a better idea in this context? (If you think some RP techniques would be applicable but not others, please explain.)