diff --git a/src/pages/guide/node/network-upgrades.mdx b/src/pages/guide/node/network-upgrades.mdx
index 70a3efc..e994cac 100644
--- a/src/pages/guide/node/network-upgrades.mdx
+++ b/src/pages/guide/node/network-upgrades.mdx
@@ -15,11 +15,24 @@ For detailed release notes and binaries, see the [Changelog](/changelog).
 
 | Release | Date | Network | Description | Priority |
 |---------|------|---------|-------------|----------|
+| [v1.4.0](https://github.com/tempoxyz/tempo/releases/tag/v1.4.0) | Mar 5, 2026 | Moderato + Mainnet | Required for T1C; introduces keychain signature migration so only V2 signatures and hashes are accepted after activation | <Badge variant="red">Required</Badge> |
 | [v1.3.1](https://github.com/tempoxyz/tempo/releases/tag/v1.3.1) | Feb 22, 2026 | Testnet + Mainnet | Fixes high-load issues and finalizes T1A/T1B hardening for expiring nonce replay protection and keychain precompile gas handling | <Badge variant="red">Required</Badge> |
 | [v1.2.0](https://github.com/tempoxyz/tempo/releases/tag/v1.2.0) | Feb 13, 2026 | Mainnet only | Fixes validation bug rejecting transactions with gas limits above ~16.7M, blocking large contract deployments | <Badge variant="red">Required</Badge> |
 
 ---
 
+## T1C
+
+| | |
+|---|---|
+| **Scope** | Security hardening, includes breaking change on keychain signatures |
+| **Release** | [v1.4.0](https://github.com/tempoxyz/tempo/releases/tag/v1.4.0) |
+| **Testnet** | Moderato: Mar 9, 2026 15:00 UTC (unix: 1773068400) |
+| **Mainnet** | Mar 12, 2026 15:00 UTC (unix: 1773327600) |
+| **Priority** | <Badge variant="red">Required</Badge> |
+
+---
+
 ## T1A / T1B
 
 | | |