diff --git a/torba/tests/client_tests/unit/test_headers.py b/torba/tests/client_tests/unit/test_headers.py
index c869a0556..5f43ca71f 100644
--- a/torba/tests/client_tests/unit/test_headers.py
+++ b/torba/tests/client_tests/unit/test_headers.py
@@ -130,15 +130,15 @@ class BasicHeadersTests(BitcoinHeadersTestCase):
         headers = MainHeaders(':memory:')
         headers.checkpoint = 100, hexlify(sha256(self.get_bytes(block_bytes(100))))
         genblocks = lambda start, end: self.get_bytes(block_bytes(end - start), block_bytes(start))
-        async with headers.checkpointed_connector() as connector:
-            connector.connect(0, genblocks(0, 10))
+        async with headers.checkpointed_connector() as buff:
+            buff.write(genblocks(0, 10))
         self.assertEqual(len(headers), 10)
-        async with headers.checkpointed_connector() as connector:
-            connector.connect(10, genblocks(10, 100))
+        async with headers.checkpointed_connector() as buff:
+            buff.write(genblocks(10, 100))
         self.assertEqual(len(headers), 100)
         headers = MainHeaders(':memory:')
-        async with headers.checkpointed_connector() as connector:
-            connector.connect(0, genblocks(0, 300))
+        async with headers.checkpointed_connector() as buff:
+            buff.write(genblocks(0, 300))
         self.assertEqual(len(headers), 300)
 
     async def test_concurrency(self):
diff --git a/torba/torba/client/baseheader.py b/torba/torba/client/baseheader.py
index ceeb97812..338c5ec8a 100644
--- a/torba/torba/client/baseheader.py
+++ b/torba/torba/client/baseheader.py
@@ -106,7 +106,6 @@ class BaseHeaders:
     @asynccontextmanager
     async def checkpointed_connector(self):
         buf = BytesIO()
-        buf.connect = lambda _, headers: buf.write(headers)
         try:
             yield buf
         finally:
diff --git a/torba/torba/client/baseledger.py b/torba/torba/client/baseledger.py
index 531c9f0a5..f19a35d58 100644
--- a/torba/torba/client/baseledger.py
+++ b/torba/torba/client/baseledger.py
@@ -313,20 +313,19 @@ class BaseLedger(metaclass=LedgerRegistry):
         return max(self.headers.height, self._download_height)
 
     async def initial_headers_sync(self):
-        target = self.network.remote_height
+        target = self.network.remote_height + 1
         current = len(self.headers)
         get_chunk = partial(self.network.retriable_call, self.network.get_headers, count=4096, b64=True)
         chunks = [asyncio.create_task(get_chunk(height)) for height in range(current, target, 4096)]
         total = 0
-        async with self.headers.checkpointed_connector() as connector:
+        async with self.headers.checkpointed_connector() as buffer:
             for chunk in chunks:
                 headers = await chunk
                 total += len(headers['base64'])
-                connector.connect(
-                    len(self.headers),
+                buffer.write(
                     zlib.decompress(base64.b64decode(headers['base64']), wbits=-15, bufsize=600_000)
                 )
-                self._download_height = len(self.headers) + connector.tell() // self.headers.header_size
+                self._download_height = current + buffer.tell() // self.headers.header_size
                 log.info("Headers sync: %s / %s", self._download_height, target)
 
     async def update_headers(self, height=None, headers=None, subscription_update=False):