Solana Schedules Alpenglow Upgrade for October 21

Solana has scheduled its Alpenglow consensus upgrade for October 21, 2026, a change intended to speed transaction finality by replacing the network’s existing validator voting system. The target is about 150 milliseconds, but actual performance will depend on network conditions. The Solana Foundation’s published timetable places the migration at Epoch 1064, expected to begin around 1500 UTC. The network is scheduled to keep its current system running for the first 5,000 slots, then switch to Alpenglow. Anza, a core Solana developer, also announced October 21 as the target date. One report said official documentation had not yet confirmed the date, while the published timetable and other reporting present it as scheduled. Alpenglow is designed to replace TowerBFT, Solana’s current consensus system. Validators now record votes on the blockchain as transactions. Under the new system, they are expected to exchange votes offchain and combine approvals into certificates used to finalize blocks after one or two voting rounds. The change is intended to reduce finality from several seconds to roughly 150 milliseconds.