Update superchain-withdrawal-pause-test.mdx

Author: sbvegan

pages/notices/superchain-withdrawal-pause-test.mdx

@@ -20,7 +20,8 @@ import { Steps, Callout } from 'nextra/components'
 # Superchain withdrawal pause test
 
 <Callout type="info">
-  Sepolia Superchain withdrawal pause test was successfully completed on **April 14th 2025**.
+  *    Sepolia Superchain withdrawal pause test was successfully completed on **April 14th 2025**.
+  *    Mainnet Superchain withdrawal pause test will happen **May 14th 2025**.
 </Callout>
 
 The Optimism Collective will be testing improved incident response features on the Sepolia Superchain.