The start of YE 39 lines up with the start of AR 942 on the Iromakuanhe Calendar.
In YE 39, Yamatai is fighting the Kuvexian War.
The Uso's Star Organization starts exploring the west. Van Banning and her associates make an attempt to trigger a Nepleslian Intervention into the west by using Alex Tasuki's mental implants to cause a massacre.
The The 4th Great Elysian Celestial Empire helps to cover this up, not wanting the Nepleslians to encroach upon the west. At the same time Raphael's mother makes a play for controlling 188604. Though this is stopped, the Uso's Star Organization is left in a precarious position: Help the Elysians or deal with the Elysians' attempt to destroy them entirely instead of just taking over the planet.
These are some new technologies that debuted in YE 39: