Mythic has posted a new feature which provides in depth details about the background lore and the game mechanics of The Necropolis of Zandri.
Both realms endeavor to have an active expedition to the Land of the Dead. The means of transport to the hostile desert wasteland are Airships. Airship expeditions are costly affairs which require resources. Only one realm will control the necessary supply lines to support the expedition, and so only one realm's flight masters will allow flight to the Land of the Dead at any one time.
Both realms' Expedition Resources are tracked on the in-game map and in the HUD. These meters grow with every Tier 4 zone control won, and every player killed in open RvR. Once a realm fills its Expedition Resource meter, it will gain control of the Land of the Dead. Its Airship Flight Masters will become active, while the other realm's will become inactive. On transfer of control, the Expedition Resource gathering pauses for 30 minutes, giving the newly winning realm unfettered access for that duration. After the initial 30 minutes, the winning realm will continue to have access but their resource meter will reset, while the losing realm's meter continues where they left off.
While only one realm can zone in and respawn in the Land of the Dead at any given time, this does not mean the opposing realm's players won't still be lurking about in Zandri. The only thing that will cast these enemy players out of the zone is respawning after dying.
Read more here.