The public testnet for ether is scheduled to be merged next month by Ropsten.
The Merge involves merging the current Proof-of-Work PoW chain with the Proof-of-Stake PoS system. The roll out is scheduled to take place on June 8. According to Core Dev preston vanloon.
The mainnet merger would happen in June, but in April, dev Tim Beiko announced on Twitter that the upgrade will be delayed to late 2022.
The announcement of Beiko was met with debate amongst the Ethereum community about when the merger would happen. An unnamed pool operator gave a guestimate of early 2023 based on code review and running test nodes.
The Merge was off schedule and not delayed according to others, including the founder of Week inEthereum News, Evan Van Ness. Van Ness said switching over to PoS requires coordination with the bomb, which is notoriously hard to predict due to the volatile nature of hashrate and price.
The process that makes mining more challenging and more unprofitable over time is called the bomb. It is considered a transition phase to ween miners off the network to be replaced by validators under a PoS system.
Van Ness stated that the delay won't be a delay and will be several weeks and not early 2023 as some had predicted. The testnet Merge is scheduled for June 8, and the call from Van Ness was proven to be accurate.
Van Loon said that the testnet is a significant step forward for the mainnet Merge later this year.
The Merge will finally roll out in Q 3 of Q 4, despite the discovery of critical bugs. At this time, no firm date is known.