diff --git a/telethon/client/dialogs.py b/telethon/client/dialogs.py
index 6a34bf99..142fd5d4 100644
--- a/telethon/client/dialogs.py
+++ b/telethon/client/dialogs.py
@@ -92,6 +92,9 @@ class DialogMethods(UserMethods):
                 if peer_id not in seen:
                     seen.add(peer_id)
                     cd = custom.Dialog(self, d, entities, messages)
+                    if cd.dialog.pts:
+                        self._channel_pts[cd.id] = cd.dialog.pts
+
                     if not ignore_migrated or getattr(
                             cd.entity, 'migrated_to', None) is None:
                         await yield_(cd)
diff --git a/telethon/client/telegrambaseclient.py b/telethon/client/telegrambaseclient.py
index 0c582659..986ee7ba 100644
--- a/telethon/client/telegrambaseclient.py
+++ b/telethon/client/telegrambaseclient.py
@@ -13,7 +13,7 @@ from ..extensions import markdown
 from ..network import MTProtoSender, ConnectionTcpFull
 from ..network.mtprotostate import MTProtoState
 from ..sessions import Session, SQLiteSession
-from ..tl import TLObject, functions
+from ..tl import TLObject, functions, types
 from ..tl.alltlobjects import LAYER
 
 DEFAULT_DC_ID = 4
@@ -219,9 +219,10 @@ class TelegramBaseClient(abc.ABC):
         self._last_ping = datetime.now()
         self._ping_delay = timedelta(minutes=1)
 
-        self._state = None
         self._updates_handle = None
         self._last_request = time.time()
+        self._channel_pts = {}
+        self._state = types.updates.State(0, 0, datetime.now(), 0, -1)
 
         # Some further state for subclasses
         self._event_builders = []
diff --git a/telethon/client/updates.py b/telethon/client/updates.py
index 2fbb13e0..9fbb4ce2 100644
--- a/telethon/client/updates.py
+++ b/telethon/client/updates.py
@@ -175,12 +175,24 @@ class UpdateMethods(UserMethods):
                         itertools.chain(update.users, update.chats)}
             for u in update.updates:
                 u._entities = entities
-                self._loop.create_task(self._dispatch_update(u))
-            return
+                self._handle_update(u)
         if isinstance(update, types.UpdateShort):
-            update = update.update
-        update._entities = {}
-        self._loop.create_task(self._dispatch_update(update))
+            self._handle_update(update.update)
+        else:
+            update._entities = getattr(update, '_entities', {})
+            self._loop.create_task(self._dispatch_update(update))
+
+        need_diff = False
+        if hasattr(update, 'pts'):
+            if self._state.pts and (update.pts - self._state.pts) > 1:
+                need_diff = True
+            self._state.pts = update.pts
+        if hasattr(update, 'date'):
+            self._state.date = update.date
+        if hasattr(update, 'seq'):
+            self._state.seq = update.seq
+
+        # TODO make use of need_diff
 
     async def _update_loop(self):
         # Pings' ID don't really need to be secure, just "random"