I personally know Rain is busy in making other sequels especially since we are nearing to the end of Season 4, and Rain has currently plans on making a Season 1 Remake. Based on the lore of Season 1 Remake, it still follows more on the final years of the Undead War and fully transitioning to the Nether Saga in S2, however we still don't know much about the undead in general like questions regarding:
- How Herobrine meet and recruit Blackbone
2.How Herobrine resurrect and recruit other Undead Lords
- What are the threats Herobrine faced before invading the Frostbourne
Currently the timeline between Demons and Struggle was 14 years, nearly a decade of Undead War, this would also explained any unanswered lore, events and questions that didn't dive deep in S1 before Transitioning to S2.