diff --git a/build/params_butterfly.go b/build/params_butterfly.go
index 4ccc9733b..096446b76 100644
--- a/build/params_butterfly.go
+++ b/build/params_butterfly.go
@@ -38,7 +38,7 @@ const UpgradeTrustHeight = -13
 const UpgradeNorwegianHeight = -14
 const UpgradeTurboHeight = -15
 const UpgradeHyperdriveHeight = -16
-const UpgradeChocolateHeight = 3700
+const UpgradeChocolateHeight = 3950
 
 func init() {
 	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2 << 30))