[Urgent] Mantle Mainnet - Upgrade op-geth to v1.6.3

Scheduled for Sep 29, 00:00 UTC - Sep 30, 00:00 UTC

Scheduled

We are upgrading our Mantle Mainnet infrastructure to op-geth v1.6.3 on 2026-09-29. This release introduces the Elysium execution client, providing compatibility with Ethereum L1 Glamsterdam through the Amsterdam execution framework. The upgrade includes upstream go-ethereum v1.17.3 with EIP-7708 ETH transfer logs, EIP-7928 block access lists, and related Engine and networking changes. Brief interruptions to RPC availability may occur on that date.

RPC Changes:
- eth_simulateV1 — Now supports Mantle fee calculation and returns eth_config safely for blobless OP Stack configurations and Amsterdam forks.
Block headers — The canonical JSON key blockAccessListHash is now used for EIP-7928 block access list references.
- Deposit encoding — Failed BVM_ETH deposit transactions are now represented with correct JSON encoding in receipts and block data.

https://github.com/mantle-xyz/op-geth/releases/tag/v1.6.3

Posted Sep 21, 2026 - 16:59 UTC

This scheduled maintenance affects: Mantle (Sepolia — JSON-RPC API).