Minecraft Caves & Cliffs Update will be split into two separate releases
And one feature has been fully postponed.
Radiant G 
The newest update coming to Minecraft for a long time was known as a single name, Caves & Cliffs. Today, developer Mojang announced that will no longer be the case. Instead, the release will be split into two separate releases: The Caves & Cliffs Summer Update and the Caves & Cliffs Holiday Update.
The Summer Update will focus on adding all of the new mobs like the Goat, the Glow Squid, and the Axolotl, as well as all the new blocks like Copper, Geodes, Dripleaf, and Glow Berries. The Holiday Update at the end of the year will be the more substantial of the two and will focus on adding the new biomes, new world height, i.e. the actual caves and cliffs.
The studio gave several reasons for the split and delay. First is quality assurance. It’s the biggest update they’ve done, and they want to release it without too many bugs. Second is technological difficulties and making sure that people can update their old Minecraft worlds to the new version. Lastly is company health. The developers made the choice to delay their release rather than crunching.
One feature has been postponed out of the Caves & Cliffs updates altogether, the new archelogy system. This will come in a future update, most likely a standalone one, but not this year, the studio said.
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