diff --git a/host/src/host/host.rs b/host/src/host/host.rs
index fff6c7a8..136ab5ef 100644
--- a/host/src/host/host.rs
+++ b/host/src/host/host.rs
@@ -104,8 +104,15 @@ pub fn preflight(
         assert!(!blob_hashs.is_empty());
         // Currently the protocol enforces the first blob hash to be used
         let blob_hash = blob_hashs[0];
+
+        let l2_chain_spec = get_network_spec(network);
+        let slot_id = block_time_to_block_slot(
+            l1_inclusion_block.header.timestamp.as_limbs()[0],
+            l2_chain_spec.genesis_time,
+            l2_chain_spec.seconds_per_slot,
+        )?;
         // Get the blob data for this block
-        let blobs = get_blob_data(&beacon_rpc_url.clone().unwrap(), l1_inclusion_block_no)?;
+        let blobs = get_blob_data(&beacon_rpc_url.clone().unwrap(), slot_id)?;
         assert!(!blobs.data.is_empty(), "blob data not available anymore");
         // Get the blob data for the blob storing the tx list
         let tx_blobs: Vec<GetBlobData> = blobs
@@ -203,6 +210,21 @@ pub fn preflight(
     })
 }
 
+// block_time_to_block_slot returns the slots of the given timestamp.
+fn block_time_to_block_slot(
+    block_time: u64,
+    genesis_time: u64,
+    block_per_slot: u64,
+) -> Result<u64> {
+    if block_time < genesis_time {
+        Err(anyhow::Error::msg(
+            "provided block_time precedes genesis time",
+        ))
+    } else {
+        Ok((block_time - genesis_time) / block_per_slot)
+    }
+}
+
 fn blob_to_bytes(blob_str: &str) -> Vec<u8> {
     match hex::decode(blob_str.to_lowercase().trim_start_matches("0x")) {
         Ok(b) => b,
@@ -225,7 +247,8 @@ fn get_blob_data(beacon_rpc_url: &str, block_id: u64) -> Result<GetBlobsResponse
     tokio_handle.block_on(async {
         let url = format!(
             "{}/eth/v1/beacon/blob_sidecars/{}",
-            beacon_rpc_url, block_id
+            beacon_rpc_url.trim_end_matches('/'),
+            block_id
         );
         let response = reqwest::get(url.clone()).await?;
         if response.status().is_success() {
@@ -588,6 +611,26 @@ mod test {
     // .unwrap();
     // }
 
+    #[test]
+    fn test_slot_block_num_mapping() {
+        let chain_spec = get_taiko_chain_spec("testnet");
+        let expected_slot = 1000u64;
+        let second_per_slot = 12u64;
+        let block_time = chain_spec.genesis_time + expected_slot * second_per_slot;
+        let block_num =
+            block_time_to_block_slot(block_time, chain_spec.genesis_time, second_per_slot)
+                .expect("block time to slot failed");
+        assert_eq!(block_num, expected_slot);
+
+        assert!(block_time_to_block_slot(
+            chain_spec.genesis_time - 10,
+            chain_spec.genesis_time,
+            second_per_slot
+        )
+        .is_err());
+    }
+
+    #[ignore]
     #[test]
     fn json_to_ethers_blob_tx() {
         let response = "{
diff --git a/lib/src/consts.rs b/lib/src/consts.rs
index ce7805e6..bcdbc435 100644
--- a/lib/src/consts.rs
+++ b/lib/src/consts.rs
@@ -60,6 +60,8 @@ pub const ETH_MAINNET_CHAIN_SPEC: Lazy<ChainSpec> = Lazy::new(|| {
         l1_contract: None,
         l2_contract: None,
         sgx_verifier_address: None,
+        genesis_time: 0u64,
+        seconds_per_slot: 1u64,
     }
 });
 
@@ -81,11 +83,13 @@ pub const TAIKO_A6_CHAIN_SPEC: Lazy<ChainSpec> = Lazy::new(|| ChainSpec {
     sgx_verifier_address: Some(
         Address::from_str("0x558E38a3286916934Cb63ced04558A52F7Ce67a9").unwrap(),
     ),
+    genesis_time: 0u64,
+    seconds_per_slot: 1u64,
 });
 
 /// The Taiko A7 specification.
 pub const TAIKO_A7_CHAIN_SPEC: Lazy<ChainSpec> = Lazy::new(|| ChainSpec {
-    chain_id: 167001,
+    chain_id: 167009,
     hard_forks: BTreeMap::from([
         (SpecId::SHANGHAI, ForkCondition::Block(0)),
         (SpecId::CANCUN, ForkCondition::TBD),
@@ -96,11 +100,13 @@ pub const TAIKO_A7_CHAIN_SPEC: Lazy<ChainSpec> = Lazy::new(|| ChainSpec {
         base_fee_max_decrease_denominator: uint!(8_U256),
         elasticity_multiplier: uint!(2_U256),
     },
-    l1_contract: Some(Address::from_str("0xC069c3d2a9f2479F559AD34485698ad5199C555f").unwrap()),
-    l2_contract: Some(Address::from_str("0x1670010000000000000000000000000000010001").unwrap()),
+    l1_contract: Some(Address::from_str("0x79C9109b764609df928d16fC4a91e9081F7e87DB").unwrap()),
+    l2_contract: Some(Address::from_str("0x1670090000000000000000000000000000010001").unwrap()),
     sgx_verifier_address: Some(
-        Address::from_str("0x558E38a3286916934Cb63ced04558A52F7Ce67a9").unwrap(),
+        Address::from_str("0x532EFBf6D62720D0B2a2Bb9d11066E8588cAE6D9").unwrap(),
     ),
+    genesis_time: 1695902400u64,
+    seconds_per_slot: 12u64,
 });
 
 pub fn get_network_spec(network: Network) -> ChainSpec {
@@ -160,6 +166,8 @@ pub struct ChainSpec {
     pub l1_contract: Option<Address>,
     pub l2_contract: Option<Address>,
     pub sgx_verifier_address: Option<Address>,
+    pub genesis_time: u64,
+    pub seconds_per_slot: u64,
 }
 
 impl ChainSpec {
@@ -176,6 +184,8 @@ impl ChainSpec {
             l1_contract: None,
             l2_contract: None,
             sgx_verifier_address: None,
+            genesis_time: 0u64,
+            seconds_per_slot: 1u64,
         }
     }
     /// Returns the network chain ID.
diff --git a/lib/src/protocol_instance.rs b/lib/src/protocol_instance.rs
index e2ef08d7..79999454 100644
--- a/lib/src/protocol_instance.rs
+++ b/lib/src/protocol_instance.rs
@@ -109,7 +109,7 @@ pub fn assemble_protocol_instance(
         transition: Transition {
             parentHash: header.parent_hash,
             blockHash: header.hash(),
-            stateRoot: input.taiko.l1_header.state_root,
+            stateRoot: header.state_root,
             graffiti: input.taiko.prover_data.graffiti,
         },
         block_metadata: BlockMetadata {
diff --git a/prove_block.sh b/prove_block.sh
index 08ba8c4d..838373f7 100755
--- a/prove_block.sh
+++ b/prove_block.sh
@@ -12,9 +12,11 @@ rangeEnd="$4"
 if [ "$chain" == "taiko_a6" ]; then
   l2Rpc="https://rpc.katla.taiko.xyz"
   l1Rpc="https://l1rpc.katla.taiko.xyz"
+  beaconRpc="https://l1beacon.hekla.taiko.xyz"
 elif [ "$chain" == "taiko_a7" ]; then
-  l2Rpc="https://rpc.internal.taiko.xyz"
-  l1Rpc="https://l1rpc.internal.taiko.xyz"
+  l2Rpc="https://rpc.hekla.taiko.xyz/"
+  l1Rpc="https://l1rpc.hekla.taiko.xyz/"
+  beaconRpc="https://l1beacon.hekla.taiko.xyz"
 else
   echo "Invalid chain name. Please use 'taiko_a6' or 'taiko_a7'."
   exit 1
@@ -59,7 +61,6 @@ if [ "$rangeEnd" == "" ]; then
   rangeEnd=$rangeStart
 fi
 
-beaconRpc="https://l1beacon.internal.taiko.xyz"
 prover="0x70997970C51812dc3A010C7d01b50e0d17dc79C8"
 graffiti="8008500000000000000000000000000000000000000000000000000000000000"