diff --git a/main.py b/main.py
index ead88f0..86d54d8 100644
--- a/main.py
+++ b/main.py
@@ -99,8 +99,8 @@ if __name__ == '__main__':
             os.remove(log_file)
         latest_block = web3.eth.get_block('latest')
         block_cache[latest_block.number] = latest_block
-        earliest_block_number = 21220693
-        preload_chat(earliest_block_number, latest_block.number)
+        start_block_number = os.getenv('START_BLOCK')
+        preload_chat(start_block_number, latest_block.number)
         room['preloaded'] = True
         room['last_block'] = latest_block.number
     else:
diff --git a/sample.env b/sample.env
index 86d4d6d..2876916 100644
--- a/sample.env
+++ b/sample.env
@@ -4,4 +4,5 @@ LOG_CONTRACT_ADDRESS=0x7aE73C498A308247BE73688c09c96B3fd06dDB84
 LOG_CONTRACT_ABI_FILE=SHIO.json
 LOG_TOPIC=0x6b81130c485ac9b98332fa40c2e57900867815b0fe1497e1a168caf930fc9c9d
 SHOW_AURA_AND_SOUL=0
+START_BLOCK=21220693
 CHANNEL_NAME=VOID
\ No newline at end of file