Solana activated Alpenglow on its live network on October 21, replacing TowerBFT and targeting irreversible transaction finality of about 150 milliseconds, down from roughly 12.8 seconds. The upgrade reached genesis slot 459,653,000 at about 14:00 UTC, with 654 validators participating and a reported handoff time of 900 milliseconds; early measurements showed finality as low as 169 milliseconds. Anza designed Alpenglow to move consensus votes offchain, changing validator voting costs from a per-transaction fee to 0.8 SOL per epoch. The upgrade does not change Solana's execution layer, transaction formats, programs or user fees. After the launch, co-founders Raj Gokal and Anatoly Yakovenko called for removing the network's Beta label, while Yakovenko had earlier questioned the development timeline and said a direct change to the vote program using the ag state machine could have cut development time in half.