BNB Chain developers have issued an urgent warning to all node operators, mandating a critical update before the scheduled Osaka/Mendel hard fork on April 28, 2026. The upgrade is set to activate on the BSC mainnet at 2:30 a.m. UTC on that date.
Node operators must upgrade their systems to BSC version 1.7.2 before the fork goes live. The developers' official notice, shared via their X account, explicitly states that failure to perform this mandatory update, including proper binary replacement and cleanup of old configuration fields, will put nodes at risk of falling out of sync with the network during the transition.
The Osaka/Mendel hard fork follows its successful activation on the BSC testnet on March 24, 2026, at block 88,379,325. The testnet deployment demonstrated improvements in reliable block construction, transaction handling at scale, network stability, and execution accuracy.
The Mendel upgrade introduces significant protocol-level changes, most notably the implementation of EIP-7825 via BEP-652. This establishes a hard, protocol-level cap on the maximum gas consumption for each transaction, set at 16,777,216 (2^24). This change ensures all nodes uniformly reject transactions exceeding the limit, replacing a previous optional soft cap mechanism to improve network stability and reliability.
The comprehensive upgrade encompasses nine BNB Evolution Proposals (BEPs). It integrates seven of the thirteen Ethereum Improvement Proposals (EIPs) from Ethereum's Fusaka scope, with six requiring a hard fork and one as a client-side RPC update. Six other EIPs were not adopted primarily due to architectural differences between the Ethereum and BSC ecosystems.
Additional BSC-specific improvements include BEP-657, which restricts the inclusion of blob transactions based on block number, and BEP-648, aimed at decreasing latency and accelerating transaction finality. These combined enhancements are designed to strengthen overall network performance, efficiency, and operational consistency for the BNB Smart Chain.
