For the first time since the launch of its network, Solana's mainnet has seen a reduction in block generation time (slot time) from 400 milliseconds to 350 milliseconds. This change was approved in May as a technical proposal known as 'SIMD-0525', and there are plans to further reduce it to 200 milliseconds in stages. In the Solana network, pre-selected validators take turns serving as 'leaders', who are responsible for bundling transactions into blocks within short time frames known as slots. Each leader is in charge of four consecutive slots, so this change will affect the intervals at which leaders rotate.