Long before Midnight was announced, I made multiple threads about Quelthalas falling to the void, for various reasons.
I imagined a great battle for Silvermoon, meanwhile Alleria turns the Sunwell to the Void, and the whole zone gets removed from the map and ported to a void world.
This revamped Quelthalas could then be resettled by both Factions in the new Void world, and used as the staging ground for exploring the new Void world.
Heck, maybe the new Silvermoon could be established as the place we run to after Azeroth is born or cracks her egg or what ever.
It still looks possible that Quelthalas might be plucked from the map and remade entirely, and just be the foothold of a larger new zone.