# Optimism withdrawal processing changes

> Relayers would retry messenger withdrawals when finalization fails because the messenger call lacks gas. Operators would use ETHLockbox for chain-specific pause checks.

- URL: https://riadefi.com/on-chain/2026-11-04-optimism-upgrade-21/
- Type: Upgrade or migration
- Stage: Proposed
- Evidence: confirmed
- Materiality: material
- Event date: 2026-11-04
- Version: 1, published 2026-11-05 (first published 2026-11-05)
- Follow-up: 2026-11-11
- Advisor-relevant: no
- Affects: Optimism canonical bridge (protocol)

## What happened

OP Labs proposed withdrawal-processing changes on November 4, 2026, with conditional mainnet execution planned for November 16.

## What changed

Relayers would retry messenger withdrawals when finalization fails because the messenger call lacks gas. Operators would use ETHLockbox for chain-specific pause checks.

## What did not change

OP Labs states that existing proofs on valid games and pending withdrawals remain valid. The named chains already use ETHLockbox, so their ETH custody stays unchanged.

## Confirmed

- OP Labs named OP Mainnet, Ink, Soneium and Unichain for the proposed mainnet execution.
- OP Labs proposed allowing anyone to delete proofs tied to dispute games that challengers won or administrators blacklisted.
- OP Labs planned Sepolia execution for November 9, 2026, and the governance veto deadline for November 11.
- OP Labs stated that mainnet execution depends on governance approval, testing and completion of the audit fix review.

## Still open

- The proposal establishes no mainnet execution.
- OP Labs had not published the final audit report in the supplied proposal.
- The mainnet date could change if testing or the audit fix review identifies problems.

## What it means for an advisor

- Ketju should review the Optimism bridge memo’s withdrawal failure handling and pause dependencies before the proposed deployment.
- Ketju should confirm execution and valid withdrawal retries before describing the changes as operative.

## Sources

1. [Optimism withdrawal and custody upgrade proposal](https://gov.optimism.io/t/upgrade-21-interop-readiness/10948) · OP Labs · 2026-11-04


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Published by Ketju Research on RIADeFi (https://riadefi.com). Educational research for financial professionals; not investment, legal, tax, or compliance advice.