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[Warhammer 40k] What's new in the lore?

Heard a new update came out for the 40k lore that had some pretty serious galaxy changing events in it. Can anyone summarize whats happened so far?
gpt
Cadia, the first line of defense against Chaos, has been completely destroyed. Like, the whole planet is destroyed. This is tied to a massive largely impassable warp storm that's now dividing the galaxy in two.

Ynnead, Eldar Death God, has been awakened, which is big. Ynnead can't manifest completely yet but has an Avatar in realspace called Yncarne. If Ynnead can reach full power, it may be able to kill Slaanesh, which would change everything.

Roboute Guilliman, founder of the Ultramarines and one of the original Primarchs, is back. This is a huge deal. He also revealed he was working with a dude named Cawl to make Primaris Space Marines, who are like the next evolution of Space Marines. Guilliman visited the Emperor and subsequently has now declared himself Lord Commander of the Imperium, basically the Emperor's Will made physical. He plans on completely reorganizing the Imperium as part of a new crusade.