Ethereum's Glamsterdam Upgrade Fails to Hit Second Target Date
The Ethereum Glamsterdam upgrade has slipped its target activation date on the Sepolia testnet for the second time. Developers had set October 6 as the new target, but with four unresolved problems still haunting its private test networks, this new deadline may not hold.
Glamsterdam's Sepolia activation was originally scheduled for August 3, but after several delays and a change in mainnet target from the first half of 2026 to the fourth quarter, it seems unlikely that October 6 will be met. The four unresolved problems include Devnet-9's finalization problem, where blocks cannot finalize normally, as well as consensus-layer bugs, execution-layer issues, and a larger validator set testing the upgrade under conditions closer to Ethereum's mainnet.
The next test to watch is Devnet-11, which was launched on September 14 with 84,000 validators. If it finalizes cleanly and holds through its Gloas fork on September 16, October 6 becomes far more credible. But if Devnet-11 repeats Devnet-9's finalization problem, expect Sepolia to move again.