diff --git a/packages/protocol/audit/sigma_prime_taiko_smart_contract_security_assessment_report_v2_0.pdf b/packages/protocol/audit/sigma_prime_taiko_smart_contract_security_assessment_report_v2_0.pdf
new file mode 100644
index 00000000000..ec6382909aa
Binary files /dev/null and b/packages/protocol/audit/sigma_prime_taiko_smart_contract_security_assessment_report_v2_0.pdf differ
diff --git a/packages/protocol/contracts/L1/TaikoData.sol b/packages/protocol/contracts/L1/TaikoData.sol
index bdf9a1372dd..f2cf2ee1b5f 100644
--- a/packages/protocol/contracts/L1/TaikoData.sol
+++ b/packages/protocol/contracts/L1/TaikoData.sol
@@ -127,7 +127,6 @@ library TaikoData {
         bytes32 blockHash;
         bytes32 stateRoot;
         bytes32 graffiti;
-        bytes32[2] __reserved;
     }
 
     /// @dev Struct representing state transition data.
diff --git a/packages/protocol/script/SetRemoteBridgeSuites.s.sol b/packages/protocol/script/SetRemoteBridgeSuites.s.sol
index 150739225f1..8bb18397cc8 100644
--- a/packages/protocol/script/SetRemoteBridgeSuites.s.sol
+++ b/packages/protocol/script/SetRemoteBridgeSuites.s.sol
@@ -23,6 +23,7 @@ contract SetRemoteBridgeSuites is DeployCapability {
     address public timelockAddress = vm.envAddress("TIMELOCK_ADDRESS");
     address public addressManagerAddress = vm.envAddress("ADDRESS_MANAGER_ADDRESS");
     uint256[] public remoteChainIDs = vm.envUint("REMOTE_CHAIN_IDS", ",");
+    address[] public remoteSignalServices = vm.envAddress("REMOTE_SIGNAL_SERVICES", ",");
     address[] public remoteBridges = vm.envAddress("REMOTE_BRIDGES", ",");
     address[] public remoteERC20Vaults = vm.envAddress("REMOTE_ERC20_VAULTS", ",");
     address[] public remoteERC721Vaults = vm.envAddress("REMOTE_ERC721_VAULTS", ",");
@@ -32,6 +33,10 @@ contract SetRemoteBridgeSuites is DeployCapability {
         require(
             remoteChainIDs.length == remoteBridges.length, "invalid remote bridge addresses length"
         );
+        require(
+            remoteChainIDs.length == remoteSignalServices.length,
+            "invalid remote SignalService addresses length"
+        );
         require(
             remoteChainIDs.length == remoteERC20Vaults.length,
             "invalid remote ERC20Vault addresses length"
@@ -51,6 +56,7 @@ contract SetRemoteBridgeSuites is DeployCapability {
             uint64 chainid = uint64(remoteChainIDs[i]);
 
             if (securityCouncilPrivateKey == 0) {
+                register(addressManagerAddress, "signal_service", remoteSignalServices[i], chainid);
                 register(addressManagerAddress, "bridge", remoteBridges[i], chainid);
                 register(addressManagerAddress, "erc20_vault", remoteERC20Vaults[i], chainid);
                 register(addressManagerAddress, "erc721_vault", remoteERC721Vaults[i], chainid);
@@ -58,6 +64,9 @@ contract SetRemoteBridgeSuites is DeployCapability {
                 continue;
             }
 
+            registerByTimelock(
+                addressManagerAddress, "signal_service", remoteSignalServices[i], chainid
+            );
             registerByTimelock(addressManagerAddress, "bridge", remoteBridges[i], chainid);
             registerByTimelock(addressManagerAddress, "erc20_vault", remoteERC20Vaults[i], chainid);
             registerByTimelock(
diff --git a/packages/protocol/test/L1/TaikoL1LibProvingWithTiers.t.sol b/packages/protocol/test/L1/TaikoL1LibProvingWithTiers.t.sol
index bd4e3042cd1..a1d35e73d61 100644
--- a/packages/protocol/test/L1/TaikoL1LibProvingWithTiers.t.sol
+++ b/packages/protocol/test/L1/TaikoL1LibProvingWithTiers.t.sol
@@ -790,8 +790,7 @@ contract TaikoL1LibProvingWithTiers is TaikoL1TestBase {
                     parentHash: parentHash,
                     blockHash: blockHash,
                     stateRoot: stateRoot,
-                    graffiti: 0x0,
-                    __reserved: [bytes32(0), bytes32(0)]
+                    graffiti: 0x0
                 });
 
                 TaikoData.TierProof memory proof;
diff --git a/packages/protocol/test/L1/TaikoL1TestBase.sol b/packages/protocol/test/L1/TaikoL1TestBase.sol
index e6b686e641e..6c311af7f58 100644
--- a/packages/protocol/test/L1/TaikoL1TestBase.sol
+++ b/packages/protocol/test/L1/TaikoL1TestBase.sol
@@ -243,8 +243,7 @@ abstract contract TaikoL1TestBase is TaikoTest {
             parentHash: parentHash,
             blockHash: blockHash,
             stateRoot: stateRoot,
-            graffiti: 0x0,
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: 0x0
         });
 
         bytes32 instance =
diff --git a/packages/protocol/test/verifiers/GuardianVerifier.t.sol b/packages/protocol/test/verifiers/GuardianVerifier.t.sol
index d9fbc135f6a..62da3490899 100644
--- a/packages/protocol/test/verifiers/GuardianVerifier.t.sol
+++ b/packages/protocol/test/verifiers/GuardianVerifier.t.sol
@@ -33,8 +33,7 @@ contract TestGuardianVerifier is TaikoL1TestBase {
             parentHash: bytes32(0),
             blockHash: bytes32(0),
             stateRoot: bytes32(0),
-            graffiti: bytes32(0),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32(0)
         });
 
         // TierProof
@@ -62,8 +61,7 @@ contract TestGuardianVerifier is TaikoL1TestBase {
             parentHash: bytes32(0),
             blockHash: bytes32(0),
             stateRoot: bytes32(0),
-            graffiti: bytes32(0),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32(0)
         });
 
         // TierProof
diff --git a/packages/protocol/test/verifiers/PseZkVerifier.t.sol b/packages/protocol/test/verifiers/PseZkVerifier.t.sol
index 3cf64da601d..27705ec19e9 100644
--- a/packages/protocol/test/verifiers/PseZkVerifier.t.sol
+++ b/packages/protocol/test/verifiers/PseZkVerifier.t.sol
@@ -51,8 +51,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32(0),
             blockHash: bytes32(0),
             stateRoot: bytes32(0),
-            graffiti: bytes32(0),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32(0)
         });
 
         // TierProof
@@ -80,8 +79,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32(0),
             blockHash: bytes32(0),
             stateRoot: bytes32(0),
-            graffiti: bytes32(0),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32(0)
         });
 
         // TierProof
@@ -133,8 +131,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -172,8 +169,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -203,8 +199,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -243,8 +238,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -282,8 +276,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -318,8 +311,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -361,8 +353,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -404,8 +395,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
@@ -444,8 +434,7 @@ contract TestPseZkVerifier is TaikoL1TestBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("23"),
             stateRoot: bytes32("34"),
-            graffiti: bytes32("1234"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("1234")
         });
 
         // TierProof
diff --git a/packages/protocol/test/verifiers/SgxVerifier.t.sol b/packages/protocol/test/verifiers/SgxVerifier.t.sol
index 98dd8f8ec8e..ed3550474eb 100644
--- a/packages/protocol/test/verifiers/SgxVerifier.t.sol
+++ b/packages/protocol/test/verifiers/SgxVerifier.t.sol
@@ -196,8 +196,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof
@@ -246,8 +245,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof
@@ -279,8 +277,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof
@@ -314,8 +311,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof
@@ -354,8 +350,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof
@@ -395,8 +390,7 @@ contract TestSgxVerifier is TaikoL1TestBase, AttestationBase {
             parentHash: bytes32("12"),
             blockHash: bytes32("34"),
             stateRoot: bytes32("56"),
-            graffiti: bytes32("78"),
-            __reserved: [bytes32(0), bytes32(0)]
+            graffiti: bytes32("78")
         });
 
         // TierProof