The Nether Update release date is 23 June 2020
I don't know when the update will be come to server. But I hope we will be see it in very short times. It may be fine that admins renew nether when they have been finished and apply new features to the server.
What's new;
Mobs: Piglins (gold hunters), Hoglins (angry rhino), Striders (lava walkers), Zoglins (Holgins - Zombie Edition)
New Nether Biomes: Basalt Deltas (Basalt Biome), Crimson Forests (Nether Trees), Soul Sand Walleys(Place of Souls), Warped Forests (Crimson Forests - Blue Edition)
New Blocks: Ancient Debris, Basalt, Blackstone, Block of Netherite, Chain, Chiseled Nether Bricks, Crying Obisidan and more.
New Items: Pigstep Music Disc, Netherite tools and armors, Lodestone compass and more.
New Structures: Basalt pillars, Bastion remnants (The House of Piglins), Some Nether fossils, Ruined Portals (Not completed and random nether portals)
More information:
https://www.minecraft.net/en-us/updates/nether/https://minecraft.gamepedia.com/Java_Edition_1.16#Mobs