Key Highlights
- Jito said Solana’s Alpenglow mainnet activation was approaching in its October 9 update, but did not confirm an activation epoch or maintenance schedule.
- Validators are advised to review client compatibility, including the recommended Jito-Solana v4.3.0-jito.0 release.
- BAM nodes will temporarily fall back to the standard Jito-Agave Block Engine, making Multiple Packet Processing (MPP) and Dynamic Block Incentives (DBI) unavailable.
Jito has issued operational guidance for Solana validators ahead of the planned Alpenglow upgrade, outlining client requirements and temporary changes to its Block Assembly Marketplace (BAM) infrastructure.
In an October 9 update, Jito said the transition was approaching but did not provide a confirmed activation epoch or maintenance schedule. Its guidance covers validator software, temporary changes to BAM services and adjustments to auction timing.
The update also included performance data, validator stake figures and details of changes to reward distribution.
Jito lists client versions ahead of Alpenglow
Jito recommends that validators review their client versions ahead of the transition. Its guidance lists the following releases:
- Jito-Solana: v4.3.0-jito.0
- Agave: v4.3.0-jito
- Firedancer (FireBAM): v26.09.5
- Frankendancer: v0.1204.40300
It also warned that production validators using dev-context-only-utils could be forked off the network. Validators should therefore check their configurations and follow Jito’s compatibility guidance before the transition.
BAM nodes will temporarily switch to block engine mode
Jito said BAM nodes will enter Maintenance Mode several days before activation and temporarily fall back to the standard Jito-Agave Block Engine.
During this period, bundles will continue to work, but BAM-specific features, including Multiple Packet Processing (MPP) and Dynamic Block Incentives (DBI), will be unavailable.
Jito said validators, FullSend users and those using standard Block Engine bundles will not need to take action.
Users relying on MPP should route oracle updates through the Transaction Processing Unit (TPU) or Block Engine. Those using DBI should switch to the legacy Block Engine bundle path during maintenance.
Jito has not confirmed the exact maintenance window, so operators using the affected features will need to monitor its announcements for the final schedule.
Shorter Solana slots require auction changes
Solana’s target slot time was reduced to 200 milliseconds at Epoch 1053 on October 9, completing the staged reduction from 400 milliseconds. The Solana Foundation lists the final step as live on mainnet.
Jito’s October 9 update said BAM’s auction interval was changing from 25 milliseconds to 20 milliseconds to accommodate the shorter slots.
The slot-time change and the Alpenglow transition are separate network developments. The former is already live, while Jito had not confirmed the activation schedule for Alpenglow in the update.
Jito details BAM performance issues
Jito’s update described several performance issues and changes intended to address them.
The company said a Linux kernel issue caused delays of 90–330 milliseconds in the first slot of some leader windows. A mitigation had been deployed and a kernel fix tested.
Jito also reported that memory compaction on trusted execution environment (TEE) hosts caused slowdowns of 7%–17%. It said a fix for false sharing reduced replay latency by about 20%.
Separately, Jito said filtering low-quality Block Engine search keys increased BAM tips per block by 15.5%.
These figures are based on Jito’s own operational update; the announcement did not provide an independent performance assessment.
BAM validator metrics and revenue distribution
At Epoch 1050, Jito reported that BAM had 164 million SOL delegated across 385 validators, representing about 37% of Solana’s network stake. FireBAM accounted for another 7.3 million SOL across 12 validators, or about 4.6% of BAM stake.
Jito said the BAM Registry had operated on testnet for more than two weeks without anomalous behaviour. Mainnet enrollment was targeted for late October, with FireBAM integration dependent on TLS support.
Jito also said preconfirmation revenue distribution was live, with the first payouts expected in October. Under the arrangement, BAM validators receive 35% of preconfirmation revenue.
Separately, Jito’s JIP-39 changed effective-stake reward bands, introduced a 2% pool-share ceiling and extended the claim window from 10 to 20 epochs. Jito reported that about 1,750 SOL in rewards went to roughly 360 validators over Epochs 1041–1050.
The registry rollout and Alpenglow transition have separate timelines, and Jito’s update did not confirm a final date for either mainnet enrollment or Alpenglow activation.
JIP-38 proposal covers JTO buybacks
In a separate development, Jito’s JIP-38 proposal was approved in July. According to an earlier report, it commits JTX revenue to JTO buybacks and burns through the fourth quarter of 2027.
The asset ticker and revenue wording should be checked against the original proposal before publication.
Jito has outlined client requirements and temporary changes to BAM operations ahead of Alpenglow, but its October 9 update did not confirm the final activation epoch or maintenance schedule.
Validators should review the applicable client requirements and monitor Jito’s latest announcements for confirmed transition details.
Also Read: Aave MCP Integrates With MetaMask Agent Wallet for DeFi Transactions
