Agave v4.3 is now the recommended version; the validator upgrade window is open. On September 21, Anza recommended that Solana mainnet validators upgrade to Agave v4.3, which includes the code required for Alpenglow—but this does not mean Alpenglow has been activated on mainnet. ① Upgrading the client and enabling features are two separate steps: first, ensure sufficient staked weight runs a compatible version before discussing feature activation. ② Alpenglow still follows the sequence: testnet → devnet → mainnet observation period. ③ For RPCs, indexers, and validators, the upgrade also involves transaction decoding, Geyser interface compatibility, and monitoring tool compatibility. ④ Any claim that “Alpenglow will go live on mainnet on September 28” lacks official confirmation and should not be treated as a fixed date. My own view: Solana is shifting from simply “releasing a version” to orchestrating a coordinated effort across clients and infrastructure. As it nears institutional-grade settlement, change management becomes as critical as performance itself. @Solana_zh @solana @anza_xyz