The code from Go Ethereum (Geth) officially enshrines the hard fork for block number 4,370,000, a time previously established by developers during an Ethereum (ETH/USD) core team discussion on September 22, CoinDesk reports.
With the Geth release, the network moves closer to implementing the first of two parts in the wider Metropolis upgrade. The addition of the code to Geth greatly increases the likelihood that the upgrade will happen at that time.
If the block time remains consistent between now and then, the hard fork – which will make previous versions incompatible with the wider Ethereum network following the upgrade trigger – will officially occur on October 17.
Anyone running an Ethereum node with Geth is requested to update their software to "ensure a smooth transition," the code release states.
In a reddit post accompanying the release, Ethereum developer Peter Szilágyi advised node operators to update their software at least a week prior to the mainnet launch.
The code release comes in spite of the recent spam attacks on the Ropsten test network, though those interruptions were not enough to deter Ethereum developers from the work on testing Byzantium.