According to the source, Ethereum core developers have reportedly set a December window for a 'Fusaka' upgrade, but there is no official confirmation on the Ethereum Foundation blog or official communication channels as of today, so the claim remains unverified (source: https://blog.ethereum.org). Traders should wait for verification via AllCoreDevs call notes or an EF announcement, since mainnet upgrade dates are typically published after testnet forks are scheduled and executed (source: https://github.com/ethereum/pm). Historical practice shows confirmed timelines such as Dencun were communicated via EF posts and coordinated across testnets before mainnet activation, creating tradable calendar catalysts once official, not before (source: https://blog.ethereum.org and https://notes.ethereum.org/@timbeiko). Until an official post or client release candidates cite a finalized block or epoch for mainnet, prioritize monitoring EF blog updates, AllCoreDevs notes, and client repos for testnet fork schedules and RC tags as timing signals (source: https://blog.ethereum.org, https://github.com/ethereum/pm, and https://github.com/ethereum/consensus-specs).