Scheduled: Tempor Mainnet & Testnet — Upgrade Tempo to v1.4.0

Scheduled for Mar 9, 00:00 - 02:00 UTC

Scheduled

Scheduled maintenance will be performed during the maintenance window to upgrade the Tempo client and apply the T1C network upgrade.

**Client Updates:**
- tempo: Upgrading to v1.4.0

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**Release Notes Summary:**

**T1C Network Upgrade Activation**
- **Moderato (testnet):** Monday, March 9 at 16:00 CET
- **Mainnet:** Thursday, March 12 at 16:00 CET

**Breaking Changes After T1C Activation**

- **Keychain signature format change:** Only V2 keychain signatures (`type 0x04`) are accepted post-T1C. Transactions using legacy V1 signatures will be rejected. Pre-T1C keys remain accessible — only the signature type and hash calculation have changed.
- **Key authorization `chain_id` wildcard removed:** `chain_id=0` is no longer valid. Key authorizations must specify the exact Tempo chain ID.
- **Precompile set updated:** Precompiles transition from Prague to Osaka at T1C activation.

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**Additional Information:**
- Full release notes: https://github.com/tempoxyz/tempo/releases/tag/v1.4.0

Posted Mar 06, 2026 - 08:57 UTC