Actually this Khemia chapter is taking place 3 years after the Cato riots and the MC left 9 months after that so this story is taking place a little over 2 years after Adastra. So the MC still has 6 years to go.
I do hope the in the chapter after this one that the MC shows up again though. Even if it's only the MC and Amicus being able to send letter/email via their portals. There is bound to be some way considering that Amicus is getting updates about what is happening on Earth (however delayed they may be).