diff --git a/library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java b/library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
index 02e271e7a4..53690d8a98 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
@@ -2241,13 +2241,18 @@ import java.util.concurrent.atomic.AtomicBoolean;
     // Ensure ad insertion metadata is up to date.
     MediaPeriodId periodIdWithAds =
         queue.resolveMediaPeriodIdForAds(timeline, newPeriodUid, contentPositionForAdResolutionUs);
+    boolean earliestCuePointIsUnchangedOrLater =
+        periodIdWithAds.nextAdGroupIndex == C.INDEX_UNSET
+            || (oldPeriodId.nextAdGroupIndex != C.INDEX_UNSET
+                && periodIdWithAds.adGroupIndex >= oldPeriodId.nextAdGroupIndex);
+    // Drop update if we keep playing the same content (MediaPeriod.periodUid are identical) and
+    // the only change is that MediaPeriodId.nextAdGroupIndex increased. This postpones a potential
+    // discontinuity until we reach the former next ad group position.
     boolean oldAndNewPeriodIdAreSame =
         oldPeriodId.periodUid.equals(newPeriodUid)
             && !oldPeriodId.isAd()
-            && !periodIdWithAds.isAd();
-    // Drop update if we keep playing the same content (MediaPeriod.periodUid are identical) and
-    // only MediaPeriodId.nextAdGroupIndex may have changed. This postpones a potential
-    // discontinuity until we reach the former next ad group position.
+            && !periodIdWithAds.isAd()
+            && earliestCuePointIsUnchangedOrLater;
     MediaPeriodId newPeriodId = oldAndNewPeriodIdAreSame ? oldPeriodId : periodIdWithAds;
 
     long periodPositionUs = contentPositionForAdResolutionUs;
diff --git a/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java b/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
index d40052a7ca..d8934c0d4e 100644
--- a/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
@@ -2400,6 +2400,56 @@ public final class ExoPlayerTest {
         .isGreaterThan(mediaSource.getCreatedMediaPeriods().get(1).windowSequenceNumber);
   }
 
+  @Test
+  public void timelineUpdateWithNewMidrollAdCuePoint_dropsPrebufferedPeriod() throws Exception {
+    Timeline timeline1 =
+        new FakeTimeline(new TimelineWindowDefinition(/* periodCount= */ 1, /* id= */ 0));
+    AdPlaybackState adPlaybackStateWithMidroll =
+        FakeTimeline.createAdPlaybackState(
+            /* adsPerAdGroup= */ 1,
+            /* adGroupTimesUs...= */ TimelineWindowDefinition
+                    .DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US
+                + 5 * C.MICROS_PER_SECOND);
+    Timeline timeline2 =
+        new FakeTimeline(
+            new TimelineWindowDefinition(
+                /* periodCount= */ 1,
+                /* id= */ 0,
+                /* isSeekable= */ true,
+                /* isDynamic= */ false,
+                /* durationUs= */ 10_000_000,
+                adPlaybackStateWithMidroll));
+    FakeMediaSource mediaSource = new FakeMediaSource(timeline1, ExoPlayerTestRunner.VIDEO_FORMAT);
+    ActionSchedule actionSchedule =
+        new ActionSchedule.Builder(TAG)
+            .pause()
+            .waitForPlaybackState(Player.STATE_READY)
+            .executeRunnable(() -> mediaSource.setNewSourceInfo(timeline2))
+            .waitForTimelineChanged(
+                timeline2, /* expectedReason= */ Player.TIMELINE_CHANGE_REASON_SOURCE_UPDATE)
+            .play()
+            .build();
+    ExoPlayerTestRunner testRunner =
+        new ExoPlayerTestRunner.Builder(context)
+            .setMediaSources(mediaSource)
+            .setActionSchedule(actionSchedule)
+            .build()
+            .start()
+            .blockUntilEnded(TIMEOUT_MS);
+
+    testRunner.assertTimelineChangeReasonsEqual(
+        Player.TIMELINE_CHANGE_REASON_PLAYLIST_CHANGED,
+        Player.TIMELINE_CHANGE_REASON_SOURCE_UPDATE,
+        Player.TIMELINE_CHANGE_REASON_SOURCE_UPDATE);
+    testRunner.assertPlayedPeriodIndices(0);
+    assertThat(mediaSource.getCreatedMediaPeriods()).hasSize(4);
+    assertThat(mediaSource.getCreatedMediaPeriods().get(0).nextAdGroupIndex)
+        .isEqualTo(C.INDEX_UNSET);
+    assertThat(mediaSource.getCreatedMediaPeriods().get(1).nextAdGroupIndex).isEqualTo(0);
+    assertThat(mediaSource.getCreatedMediaPeriods().get(2).adGroupIndex).isEqualTo(0);
+    assertThat(mediaSource.getCreatedMediaPeriods().get(3).adGroupIndex).isEqualTo(C.INDEX_UNSET);
+  }
+
   @Test
   public void repeatedSeeksToUnpreparedPeriodInSameWindowKeepsWindowSequenceNumber()
       throws Exception {