diff --git a/operator/runtime/mainnet/src/configs/mod.rs b/operator/runtime/mainnet/src/configs/mod.rs
index c5975427..805552a1 100644
--- a/operator/runtime/mainnet/src/configs/mod.rs
+++ b/operator/runtime/mainnet/src/configs/mod.rs
@@ -1190,10 +1190,14 @@ parameter_types! {
     };
 }
 
+parameter_types! {
+    pub const FreeHeadersInterval: u32 = 32; // 1 epoch = 6.4 minutes
+}
+
 impl snowbridge_pallet_ethereum_client::Config for Runtime {
     type RuntimeEvent = RuntimeEvent;
     type ForkVersions = ChainForkVersions;
-    type FreeHeadersInterval = ();
+    type FreeHeadersInterval = FreeHeadersInterval;
     type WeightInfo = mainnet_weights::snowbridge_pallet_ethereum_client::WeightInfo<Runtime>;
 }
 
diff --git a/operator/runtime/stagenet/src/configs/mod.rs b/operator/runtime/stagenet/src/configs/mod.rs
index 8ae2c091..d1d37a88 100644
--- a/operator/runtime/stagenet/src/configs/mod.rs
+++ b/operator/runtime/stagenet/src/configs/mod.rs
@@ -1189,10 +1189,14 @@ parameter_types! {
     };
 }
 
+parameter_types! {
+    pub const FreeHeadersInterval: u32 = 32; // 1 epoch = 6.4 minutes
+}
+
 impl snowbridge_pallet_ethereum_client::Config for Runtime {
     type RuntimeEvent = RuntimeEvent;
     type ForkVersions = ChainForkVersions;
-    type FreeHeadersInterval = ();
+    type FreeHeadersInterval = FreeHeadersInterval;
     type WeightInfo = stagenet_weights::snowbridge_pallet_ethereum_client::WeightInfo<Runtime>;
 }
 
diff --git a/operator/runtime/testnet/src/configs/mod.rs b/operator/runtime/testnet/src/configs/mod.rs
index af392689..67df3642 100644
--- a/operator/runtime/testnet/src/configs/mod.rs
+++ b/operator/runtime/testnet/src/configs/mod.rs
@@ -1190,10 +1190,14 @@ parameter_types! {
     };
 }
 
+parameter_types! {
+    pub const FreeHeadersInterval: u32 = 32; // 1 epoch = 6.4 minutes
+}
+
 impl snowbridge_pallet_ethereum_client::Config for Runtime {
     type RuntimeEvent = RuntimeEvent;
     type ForkVersions = ChainForkVersions;
-    type FreeHeadersInterval = ();
+    type FreeHeadersInterval = FreeHeadersInterval;
     type WeightInfo = testnet_weights::snowbridge_pallet_ethereum_client::WeightInfo<Runtime>;
 }
 
diff --git a/test/.papi/metadata/datahaven.scale b/test/.papi/metadata/datahaven.scale
index 6b9fb94b..08f0c18c 100644
Binary files a/test/.papi/metadata/datahaven.scale and b/test/.papi/metadata/datahaven.scale differ