Lantern was the second JSAer kicked upstairs in 1941, after All-Star Comics #7 when he got his own title (Flash was the first after #6). In the same issue, Hourman was dropped (referred to as taking a leave of absence), and they were replaced by Starman and Dr. Midnite in #8. He and the Flash returned to replace Starman and The Spectre in 1944's issue 24, and stayed until the title switched to a Western. So GL was gone for over 3 years.