The Great Void War?

So from an earlier post talking about the timeline of major Runeterran events, a Rioter mentioned that the Great Void War that had caused the creation of Vastaya was "way earlier" and one of the first events in the timeline. But what does this mean exactly? With the new Void lore, it's clear what happened at the Fall of Icathia, which definitely WASN'T the Void War, so what exactly was it?

Another thing, they mention how Icathia was taken by the fabled Golden Queen we saw in Varus's lore, making it seem though she basically founded the Shuriman empire with the army she amassed to fight off the Darkin. But...didn't the Darkin war transpire AFTER Shurima's fall?!? How does that work?!?!

Either way, love the new lore, just have a few questions regarding the timeline of events!