diff --git a/backend/scheduler.py b/backend/scheduler.py
index 52f486e..e3494bf 100644
--- a/backend/scheduler.py
+++ b/backend/scheduler.py
@@ -3,7 +3,7 @@ import os
 
 from dataclasses import dataclass
 from datetime import date, timedelta
-from test_window import get_shift_sequence_with_capacity, is_off_day, next_window_start_date
+from test_window import get_shift_sequence_with_capacity, get_shift_capacity_for_date, is_off_day, next_window_start_date
 from test_bundle import Test, TestBundle, build_test_bundles, bundle_pair_lookup
 
 DUT = (os.getenv("DUT") or "DUT").strip()
@@ -287,28 +287,50 @@ class Scheduler:
         window: ScheduleWindow,
         bundles: list[TestBundle],
     ) -> None:
+        # Build per-shift remaining capacity
+        shift_remaining = [
+            get_shift_capacity_for_date(day, self.holiday_dates, self.daytime_testing_today).get(shift_idx, 0)
+            for day, shift_idx in window.shifts
+        ]
+        current_shift_pos = 0
+        sequence_in_shift = 0
+
         for bundle in bundles:
             bundle_key = (bundle.index, bundle.device)
             if bundle_key in self.scheduled_bundle_keys:
                 continue
             self.scheduled_bundle_keys.add(bundle_key)
 
-            for idx, test in enumerate(bundle.tests):
+            for test in bundle.tests:
                 schedule_key = f"{test}:{bundle.device}"
                 if schedule_key in self.scheduled_test_ids:
                     continue
                 self.scheduled_test_ids.add(schedule_key)
 
+                test_minutes = self._get_test_minutes(test, bundle.device)
+
+                # Advance past any shift that can't fit this test
+                while current_shift_pos < len(window.shifts) and shift_remaining[current_shift_pos] < test_minutes:
+                    current_shift_pos += 1
+                    sequence_in_shift = 0
+
+                if current_shift_pos >= len(window.shifts):
+                    break
+
+                shift_day, shift_idx = window.shifts[current_shift_pos]
+                sequence_in_shift += 1
+                shift_remaining[current_shift_pos] -= test_minutes
+                window.remaining_minutes -= test_minutes
+
                 self.schedule.append(
                     ScheduleEntry(
                         test_id=test,
                         device=bundle.device,
-                        scheduled_date=str(window.shifts[0][0]),
-                        shift_index=window.shifts[0][1],
-                        sequence_in_shift=idx + 1,
+                        scheduled_date=str(shift_day),
+                        shift_index=shift_idx,
+                        sequence_in_shift=sequence_in_shift,
                     )
                 )
-                window.remaining_minutes -= self._get_test_minutes(test, bundle.device)
         
 
     def _get_test_minutes(self, test_id: str, device: str) -> int: