diff --git a/apps/m3u/serializers.py b/apps/m3u/serializers.py
index 0d65276b..587d98cb 100644
--- a/apps/m3u/serializers.py
+++ b/apps/m3u/serializers.py
@@ -7,6 +7,7 @@ from apps.channels.models import ChannelGroup, ChannelGroupM3UAccount
 from apps.channels.serializers import (
     ChannelGroupM3UAccountSerializer,
 )
+from datetime import timezone as dt_tz
 import logging
 import json
 
@@ -214,10 +215,14 @@ class M3UAccountSerializer(serializers.ModelSerializer):
 
         # Surface default profile's exp_date for the form.
         # Use prefetch cache (obj.profiles.all()) to avoid an extra query per account.
+        # Always emit a Z-suffix UTC string so JS new Date() never misinterprets it as local.
         default_profile = next((p for p in instance.profiles.all() if p.is_default), None)
-        data["exp_date"] = (
-            default_profile.exp_date.isoformat() if default_profile and default_profile.exp_date else None
-        )
+        exp = default_profile.exp_date if default_profile else None
+        if exp:
+            exp_utc = exp.astimezone(dt_tz.utc) if exp.tzinfo else exp.replace(tzinfo=dt_tz.utc)
+            data["exp_date"] = exp_utc.strftime('%Y-%m-%dT%H:%M:%SZ')
+        else:
+            data["exp_date"] = None
 
         return data
 
@@ -286,12 +291,19 @@ class M3UAccountSerializer(serializers.ModelSerializer):
                 memberships_to_update, ["enabled"]
             )
 
-        # Write exp_date through to the default profile
+        # Write exp_date through to the default profile.
+        # Use a fresh DB query (not the prefetch cache) so we get the profile
+        # object AFTER the post_save signal (create_profile_for_m3u_account)
+        # has already updated max_streams, avoiding a stale-value overwrite.
         if exp_date != "__NOT_SET__":
             default_profile = instance.profiles.filter(is_default=True).first()
             if default_profile:
                 default_profile.exp_date = exp_date
-                default_profile.save()
+                default_profile.save(update_fields=['exp_date'])
+            # Invalidate the profiles prefetch cache so to_representation
+            # sees the updated exp_date rather than the pre-request snapshot.
+            if '_prefetched_objects_cache' in instance.__dict__:
+                instance._prefetched_objects_cache.pop('profiles', None)
 
         return instance
 
@@ -342,7 +354,9 @@ class M3UAccountSerializer(serializers.ModelSerializer):
         expiring = [p.exp_date for p in obj.profiles.all() if p.is_active and p.exp_date]
         if not expiring:
             return None
-        return min(expiring).isoformat()
+        exp = min(expiring)
+        exp_utc = exp.astimezone(dt_tz.utc) if exp.tzinfo else exp.replace(tzinfo=dt_tz.utc)
+        return exp_utc.strftime('%Y-%m-%dT%H:%M:%SZ')
 
     def get_all_expirations(self, obj):
         """Return exp_date info for every profile that has one (for tooltip)."""
@@ -355,7 +369,7 @@ class M3UAccountSerializer(serializers.ModelSerializer):
             {
                 "profile_id": p.id,
                 "profile_name": p.name,
-                "exp_date": p.exp_date.isoformat(),
+                "exp_date": (p.exp_date.astimezone(dt_tz.utc) if p.exp_date.tzinfo else p.exp_date.replace(tzinfo=dt_tz.utc)).strftime('%Y-%m-%dT%H:%M:%SZ'),
                 "is_active": p.is_active,
             }
             for p in profiles
diff --git a/frontend/src/components/forms/M3U.jsx b/frontend/src/components/forms/M3U.jsx
index 423b2a05..c8caeaef 100644
--- a/frontend/src/components/forms/M3U.jsx
+++ b/frontend/src/components/forms/M3U.jsx
@@ -46,6 +46,7 @@ const M3U = ({
 
   const [playlist, setPlaylist] = useState(null);
   const [file, setFile] = useState(null);
+  const [expDate, setExpDate] = useState(null);
   const [profileModalOpen, setProfileModalOpen] = useState(false);
   const [groupFilterModalOpen, setGroupFilterModalOpen] = useState(false);
   const [filterModalOpen, setFilterModalOpen] = useState(false);
@@ -70,7 +71,6 @@ const M3U = ({
       stale_stream_days: 7,
       priority: 0,
       enable_vod: false,
-      exp_date: null,
     },
 
     validate: {
@@ -103,8 +103,8 @@ const M3U = ({
             ? m3uAccount.priority
             : 0,
         enable_vod: m3uAccount.enable_vod || false,
-        exp_date: m3uAccount.exp_date ? new Date(m3uAccount.exp_date) : null,
       });
+      setExpDate(m3uAccount.exp_date ? new Date(m3uAccount.exp_date) : null);
 
       // Determine schedule type from existing data
       setScheduleType(
@@ -122,6 +122,7 @@ const M3U = ({
       setPlaylist(null);
       form.reset();
       setScheduleType('interval');
+      setExpDate(null);
     }
   }, [m3uAccount]);
 
@@ -134,13 +135,13 @@ const M3U = ({
   const onSubmit = async () => {
     const { create_epg, ...values } = form.getValues();
 
-    // Convert exp_date Date object to ISO string for the API
+    // Convert exp_date (from controlled state) to ISO string for the API
     if (values.account_type === 'XC') {
       // XC accounts have exp_date auto-managed server-side; don't send it
       delete values.exp_date;
-    } else if (values.exp_date instanceof Date) {
-      values.exp_date = values.exp_date.toISOString();
-    } else if (!values.exp_date) {
+    } else if (expDate instanceof Date) {
+      values.exp_date = expDate.toISOString();
+    } else {
       values.exp_date = null;
     }
 
@@ -387,8 +388,8 @@ const M3U = ({
                     placeholder="No expiration"
                     clearable
                     valueFormat="MMM D, YYYY h:mm A"
-                    {...form.getInputProps('exp_date')}
-                    key={form.key('exp_date')}
+                    value={expDate}
+                    onChange={(v) => setExpDate(v ? new Date(v) : null)}
                   />
                 </>
               )}