Solana is rolling out its first mainnet slot-time reduction, lowering the target from about 400 milliseconds to 350 milliseconds starting at Epoch 1020. Brennan Watt said the feature uses a delayed activation path, moving from pending status in one Epoch to activation in the next and becoming fully effective by the following Epoch, creating a transition window for applications tied to timing assumptions. Some SDK constants, including DEFAULT_MS_PER_SLOT, have not yet been updated and will be refreshed in a later release, so developers relying on those values matching mainnet behavior were advised to add adaptation logic around Epoch slot boundaries. Watt said Solana eventually plans to move such network parameters on-chain so clients can query them directly, and that the team expects most nodes to reach a two-slot latency target in most cases, with related limits set to be eased further in Anza v4.3.