According to the source, a social post claims an Ethereum 'Fusaka upgrade' cleared a final test, but this upgrade name does not appear in Ethereum Foundation’s official upgrade communications or roadmap. source: Ethereum Foundation The latest confirmed scaling upgrade is Dencun, which activated EIP-4844 (proto-danksharding) on mainnet on 2024-03-13 to lower Layer-2 data costs. source: Ethereum Foundation The next workstream under discussion is Pectra (Prague + Electra), tracked via public AllCoreDevs calls and repositories, and no Ethereum Foundation announcement has confirmed any 'Fusaka' release. source: Ethereum AllCoreDevs; Ethereum Foundation Trading-wise, treat the claim as unconfirmed and wait for an Ethereum Foundation or client team announcement before positioning; monitor ETH spot/derivatives, gas fees, and L2 fee metrics that moved around Dencun. source: Ethereum Foundation; Ethereum AllCoreDevs

According to the source, there is an unverified claim that the Ethereum Foundation will begin degrading the Holesky testnet with node operators shutting down nodes over roughly 10 days; traders should wait for confirmation via official Ethereum Foundation channels before positioning, as third-party posts are not authoritative (source: https://blog.ethereum.org, https://github.com/ethereum/pm, https://ethereum.org/en/developers/docs/networks/testnets). Official Ethereum testnet changes and deprecations are typically announced on the Ethereum Foundation blog and coordinated through AllCoreDevs and client-team repositories, which act as the canonical record for timelines and procedures (source: https://blog.ethereum.org, https://github.com/ethereum/pm). Holesky is a public Ethereum testnet intended for large-scale validator and infrastructure testing, and testnet events do not affect mainnet ETH balances or mainnet consensus, limiting direct market risk from testnet-only actions (source: https://ethereum.org/en/developers/docs/networks/testnets). If a Holesky wind-down were officially confirmed, developers and validators would likely migrate additional workloads to Sepolia, the other recommended testnet for application flows, which can temporarily impact devops pipelines but not mainnet activity or user funds (source: https://ethereum.org/en/developers/docs/networks/testnets). Traders should monitor the Ethereum Foundation blog, AllCoreDevs coordination repo, and client releases for any dated Holesky notice and adjust only after an official publication is live (source: https://blog.ethereum.org, https://github.com/ethereum/pm).

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).