Recap of Our Recent Call – Key Q&A
Hey everyone,
We had a great discussion on our recent call (video, trascript), where Péter shared key technical updates.
To keep everyone aligned, here’s a summary of the key Q&A from the session.
Feel free to drop any follow-up questions or thoughts in the comments!
TL;DR 
Sequencer Downtime: A new permissionless batch submission feature allows block production and proof submission if the Scroll sequencer goes down.
Testnet Upgrades: Phases 1 & 2 of Scroll testnet updates were completed successfully, with results informing the final DAO proposal.
Testing & Ethereum Delays: Multi-stage testing is ongoing, and Ethereum’s upgrade delay to May actually benefits Scroll by reducing conflicts.
Proposal Timeline: Voting starts April 1, with a 3-day review and 7-day voting period. If approved, the security council will execute the upgrade.
Node Operators: Running the new MPT version and reporting errors is highly encouraged!
Future Data Strategy: Exploring state diffs vs. transaction data, with potential for a hybrid approach in the future.
Key Q&A Recap
Question 1: What happens if the sequencer goes down? How does transaction processing compare to OP or Arbitrum?
Péter: Scroll introduced a permissionless batch submission mechanism. If the Scroll sequencer is down for a set period, anyone can start producing blocks using open-source software and submit a ZK proof to L1. This ensures continued functionality but requires technical expertise.
Question 2: Will withdrawals from Scroll be affected, and will they be tested?
Péter: Withdrawals will be delayed for a short period of time. Regarding testnet availability, Scroll is actively rolling out updates on the testnet, where developers and partners can test the changes.
- Phase 1 completed on March 11
- Phase 2 completed on March 13
So far, everything is running smoothly, and insights from this will be included in the final DAO proposal.
Question 3: How did the first phase of testing go? Will Ethereum’s delays impact the Scroll upgrade?
Péter: Scroll follows a multi-stage testing process:
- Unit tests & audits
- Internal devnet (fresh Scroll instance, transaction simulation)
- Sepolia & public testnets
Ethereum’s upgrade delay (April → May) is actually beneficial, avoiding conflicts with Scroll’s upgrade. No issues were detected during the Pectra upgrade testing on Scroll Sepolia.
Question 4: When does the proposal go live for voting? What happens after that?
Péter:
- Updated proposal is planned to be submitted by the end of March
- Official proposal goes live on April 1
- 3-day review period→ 7-day voting period
- If passed, the Security Council (announced on X (Twitter) & the blog) will execute the upgrade
Question 5: Can node operators help with testing the upgrade?
Péter: Absolutely! The testnet node for Euclid was recently released. We highly encourage node operators to:
- Run the new MPT version of the node
- Report any errors or feedback
(Currently, the node supports two modes: a) The old Zktrie​ commitment b) The new MPT commitment.)
Question 6: Future plans - Will Scroll switch from transaction data to state diffs?
Péter: The debate between transaction data & state diffs may resurface as rollup bandwidth increases.
- The Fusaka upgrade (post-Pectra) aims to increase Ethereum’s block throughput, which could affect this decision.
- Scroll is exploring a hybrid approach to dynamically switch between transaction data & state diffs, though trade-offs exist (e.g., historical data loss).
Check out the full conversation here:
Recording: 
Watch here
Transcript: Read here
Have more questions? Feel free to drop them below! 