Alot of costuming organizations require "age of majority", that being 18. Sometimes it's because we have to be responsible to not only ourselves but the club at large, and some under 18's can't handle that responsibility
But that doesn't mean you can't distinguish yourself as a valuble UM and when you hit 18, be welcomed in as a flying-colors OM! Take the oppurtunity to really smash your kit out of the park, get mentored by your local clan members. Just because you're not official DOESN'T mean you're not a part of this club! Good luck on your kit Centhozabal!