Ethereum schedules Glamsterdam for the Sepolia test network

In an announcement dated 28 September, Ethereum’s protocol team scheduled Glamsterdam for Sepolia on 6 October at 13:53:36 UTC. The release explicitly covers the test network and leaves Hoodi and mainnet activation times to later announcements. It tells Sepolia node operators to update both execution and consensus clients before the scheduled change. Ethereum testnet announcement.

The upgrade includes enshrined proposer-builder separation and block-level access lists. The former moves parts of block production into the consensus protocol; the latter records state access to support more efficient validation. Glamsterdam also changes gas accounting, including the costs of creating and accessing state. Ethereum’s announcement asks application developers to test contracts and gas estimation, particularly where code relies on fixed gas assumptions. The schedule is evidence of a coordinated testnet deployment plan, not confirmation that the main network has adopted those rules. Mainnet users have no action to take as a result of this Sepolia announcement, according to the protocol team. Ethereum testnet announcement.