Sagan 4 Alpha is the original Sagan 4 project started in 2006. It is the largest of the Sagan 4 projects, and it is currently in Week 27.
Sagan 4 Beta is a fan-made reboot of the project started in 2019, which has since been elevated into an official Sagan 4 project. It splits off from the timeline at the end of Week 1 and is currently in Week 4.
Mason is an offshoot of Sagan 4 Alpha which split from the project in 2010, about life that has been seeded on the planet's icy moon. It is currently closed, but work is being done to prepare it for reopening.