In an effort to further player development and deepen the player pool from which elite players are developed, the Elite Clubs National League introduced “Composite Events” for ECNL member clubs beginning in the 2015-16 season. These new and unique events are established to provide players from ECNL Member Clubs with additional competition structures for mixed age group teams, teams competing in non-traditional seasons, and for other development purposes.
The 2017-18 ECNL competition season will include one Composite Event
http://www.eliteclubsnationalleague.com/composite-events-17-18/