Changelog update

CHANGELOG.md

@@ -6,9 +6,14 @@ Update this for each program release and mainnet deployment.
 
 ### v0.21.1, 2024-1-
 
-- Fix extreme interest rates for tokens with borrows but nearly no deposits.
+- Prevent withdraw operations from bringing token utilization over 100%.
+- Prevent extreme interest rates for tokens with borrows but near zero deposits.
 
-### v0.21.0, 2023-12-
+## mainnet
+
+### v0.21.0, 2023-12-13
+
+Deployment: Dec 13, 2023 at 09:02:46 Central European Standard Time, https://explorer.solana.com/tx/47BBFEugtHYciK5jHVzVtXawc7oyXKzX8o5V4ERXX3Cb7AZqmr8w6uDrFPRpyJRDccRWtuno8g2micqaFoSLC1EL
 
 - Introduce deposit limits (#806)
 
@@ -57,8 +62,6 @@ Update this for each program release and mainnet deployment.
 - Significantly reduce program heap use (#787, #785)
 - Reduce compute use of OpenBook health computations (#750)
 
-## mainnet
-
 ### v0.20.0, 2023-11-8
 
 Deployment: Nov 8, 2023 at 10:44:24 Central European Standard Time, https://explorer.solana.com/tx/4LM5NJAa71tjjKT4a7MXVVsautU1DNvszbXp2ufeps9gMrksRh9pURRiacoyCEgW9gdBYJb1W3TL6o7dzDcUVmVH