According to CoinDesk, Ethereum developers have confirmed the dates for changes on two key test networks in a blog post regarding Dencun, the largest upgrade planned for this year. Dencun is a major upgrade or "hard fork" of the Ethereum blockchain that will implement "proto-danksharding," a technical feature that will reduce the cost of layer 2 transactions and make data on the blockchain cheaper. Prior to triggering on the main chain, developers will rehearse protocol changes on Sepolia and Holesky test networks (testnets) on January 30th and February 7th respectively. Previously, an upgrade on the Goerli test network went live successfully last week despite some minor issues. Dencun will be triggered at 22:51 UTC and epoch 132608 on Sepolia. If everything goes as planned, Dencun's final testing will take place at 11:34 UTC on February 7th with epoch number 950272 on Holesky. Afterward, developers will determine the deployment date of Dencun on the Ethereum mainnet with a current target set for late February or early March.