This seems to be the main Earth which other E-ST have splintered from. We have transmissions featuring a few of the more prominent captains over the period 2260-2375 relative time.

Also called the AOS or the Kelvin timeline, takes place within an E-ST where Vulcan was destroyed within subject Captain Kirk's time.

Sometime called the Mirror Verse, it features many of the same echo points from E-ST1966, however many of the events of that earth have been altered.

A series of transmissions, all clearly taking place within E-ST but few feature the same echo points and cannot conclusively be placed in any other E-ST archive category.