Where the slot-time gates stand
Solana's slot-time plan calls for four separate 50-millisecond reductions from the current 400-millisecond target. Each step moves the network closer to 200-millisecond slots, and the network can pause the sequence if block skip rates start climbing.
The 350-millisecond and 300-millisecond gates are pending mainnet activation. Testnet has them scheduled for epochs 1000 and 1002; devnet has them at epochs 1115 and 1118. The 250-millisecond gate activated on testnet at epoch 1004 but remains pending on devnet. The final 200-millisecond gate is still pending on testnet.
So of the four gates, only the first two have dates assigned on both testnet and devnet. The last one hasn't cleared testnet at all.
The rent cut that isn't live yet
The advertised 90% rent reduction on lamports_per_byte — from 6,960 down to 696 — describes the completed sequence, not the first step. All five gates in that reduction were inactive as of Aug. 17. The intermediate values run 6,333, 5,080, 2,575, and 1,322.
The headline number is the end state. The process hasn't started on any network, which means the 90% figure is a destination, not something users can expect from the Aug. 17 date.
What 4.2 actually carries
The v1 transaction plan raises the maximum payload from 1,232 bytes to 4,096 bytes, but only for the new format. Legacy and v0 transaction limits stay unchanged. That's a narrower change than it might look at first glance.
Agave 4.2 also includes the code needed to test Alpenglow, the consensus overhaul that promises to cut transaction finality from TowerBFT's current 12.8 seconds to as low as 100–150 milliseconds. But Alpenglow is not part of the 4.2 mainnet activation. It's expected in Agave 4.3, which targets October 2026.
The Aug. 17 date doesn't bundle the 90% rent cut, the 4,096-byte transactions, and the 200-millisecond slots into one live package
