The roll-out of Ethereum 2.0 won’t come all at once. Instead, it’ll be released in three phases, each of which accompanies distinct features to ensure the success of the new Ethereum.
The first phase, or phase 0, will be dedicated to the release of the beacon chain since it’s central to the functionality of shard chains. There won’t be shard chains just yet, but the beacon chain will begin accepting validators (i.e., stakers) through a one-way deposit contract.
It’s important to note that all registered validators who stake their ETH won’t be able to “unstake” until shard chains are fully implemented. That means ETH from validators will be locked up until the next phase.
The Eth2 deposit contract reached the required minimum of 524,288 ETH to launch. Phase 0 begins on the 1st of December, 2020.
The next phase is actually a mix of two phases: phase 1 and phase 1.5. Phase 1 will introduce shard chains, which will allow validators to create blocks on the blockchain through PoS. Phase 1.5 is when Ethereum’s mainnet will officially introduce the shard chains and begin transitioning away from PoW to PoS.
Phase 1/1.5 is expected to roll out during 2021.
The final phase will be phase 2, which is when Ethereum 2.0 will support fully formed shards and become the official Ethereum network. Shard chains will be able to work with smart contracts as well, allowing developers of Dapps and other technologies to integrate seamlessly with Ethereum 2.0.
Phase 2 is expected to roll out in 2021 or later.