diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
index dc1162ab1..de0ce4b08 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
@@ -552,6 +552,7 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
         config.getDynamoDbMigrationCrawlerConfiguration().getChunkIntervalMs(),
         accountsCrawlerChunkPreReadExecutor,
         dynamicConfigurationManager);
+    accountDynamoDbMigrationCrawler.setDedicatedDynamoMigrationCrawler(true);
 
     DeletedAccountsTableCrawler deletedAccountsTableCrawler = new DeletedAccountsTableCrawler(deletedAccountsManager, deletedAccountsDirectoryReconcilers, cacheCluster, recurringJobExecutor);
     MigrationRetryAccountsTableCrawler migrationRetryAccountsTableCrawler = new MigrationRetryAccountsTableCrawler(
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/storage/AccountDatabaseCrawler.java b/service/src/main/java/org/whispersystems/textsecuregcm/storage/AccountDatabaseCrawler.java
index c96bd1203..754f2ab74 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/storage/AccountDatabaseCrawler.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/storage/AccountDatabaseCrawler.java
@@ -48,6 +48,9 @@ public class AccountDatabaseCrawler implements Managed, Runnable {
   private AtomicBoolean running = new AtomicBoolean(false);
   private boolean finished;
 
+  // temporary to control behavior during the Postgres → Dynamo transition
+  private boolean dedicatedDynamoMigrationCrawler;
+
   public AccountDatabaseCrawler(AccountsManager accounts,
       AccountDatabaseCrawlerCache cache,
       List<AccountDatabaseCrawlerListener> listeners,
@@ -128,7 +131,7 @@ public class AccountDatabaseCrawler implements Managed, Runnable {
 
     try (Timer.Context timer = processChunkTimer.time()) {
 
-      final boolean useDynamo = dynamicConfigurationManager.getConfiguration()
+      final boolean useDynamo = !dedicatedDynamoMigrationCrawler && dynamicConfigurationManager.getConfiguration()
           .getAccountsDynamoDbMigrationConfiguration()
           .isDynamoCrawlerEnabled();
 
@@ -212,6 +215,10 @@ public class AccountDatabaseCrawler implements Managed, Runnable {
     }
   }
 
+  public void setDedicatedDynamoMigrationCrawler(final boolean dedicatedDynamoMigrationCrawler) {
+    this.dedicatedDynamoMigrationCrawler = dedicatedDynamoMigrationCrawler;
+  }
+
   private synchronized void sleepWhileRunning(long delayMs) {
     if (running.get()) Util.wait(this, delayMs);
   }
diff --git a/service/src/test/java/org/whispersystems/textsecuregcm/tests/storage/AccountDatabaseCrawlerTest.java b/service/src/test/java/org/whispersystems/textsecuregcm/tests/storage/AccountDatabaseCrawlerTest.java
index e489c4f8c..6b2743d7b 100644
--- a/service/src/test/java/org/whispersystems/textsecuregcm/tests/storage/AccountDatabaseCrawlerTest.java
+++ b/service/src/test/java/org/whispersystems/textsecuregcm/tests/storage/AccountDatabaseCrawlerTest.java
@@ -5,21 +5,38 @@
 
 package org.whispersystems.textsecuregcm.tests.storage;
 
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.params.ParameterizedTest;
-import org.junit.jupiter.params.provider.ValueSource;
-import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicAccountsDynamoDbMigrationConfiguration;
-import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicConfiguration;
-import org.whispersystems.textsecuregcm.storage.*;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyLong;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.verifyZeroInteractions;
+import static org.mockito.Mockito.when;
+
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.ExecutorService;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.ArgumentMatchers.*;
-import static org.mockito.Mockito.*;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicAccountsDynamoDbMigrationConfiguration;
+import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicConfiguration;
+import org.whispersystems.textsecuregcm.storage.Account;
+import org.whispersystems.textsecuregcm.storage.AccountCrawlChunk;
+import org.whispersystems.textsecuregcm.storage.AccountDatabaseCrawler;
+import org.whispersystems.textsecuregcm.storage.AccountDatabaseCrawlerCache;
+import org.whispersystems.textsecuregcm.storage.AccountDatabaseCrawlerListener;
+import org.whispersystems.textsecuregcm.storage.AccountDatabaseCrawlerRestartException;
+import org.whispersystems.textsecuregcm.storage.AccountsManager;
+import org.whispersystems.textsecuregcm.storage.DynamicConfigurationManager;
 
 class AccountDatabaseCrawlerTest {
 
@@ -132,7 +149,43 @@ class AccountDatabaseCrawlerTest {
     verify(cache, times(1)).isAccelerated();
     verify(cache, times(1)).releaseActiveWork(any(String.class));
 
-    verifyZeroInteractions(account1);
+    verifyNoInteractions(account1);
+
+    verifyNoMoreInteractions(account2);
+    verifyNoMoreInteractions(accounts);
+    verifyNoMoreInteractions(listener);
+    verifyNoMoreInteractions(cache);
+  }
+
+  @ParameterizedTest
+  @ValueSource(booleans = {true, false})
+  void testCrawlChunk_useDynamoDedicatedMigrationCrawler(final boolean dedicatedMigrationCrawler) throws Exception {
+    crawler.setDedicatedDynamoMigrationCrawler(dedicatedMigrationCrawler);
+
+    when(dynamicAccountsDynamoDbMigrationConfiguration.isDynamoCrawlerEnabled()).thenReturn(true);
+    when(cache.getLastUuid()).thenReturn(Optional.of(ACCOUNT1));
+    when(cache.getLastUuidDynamo()).thenReturn(Optional.of(ACCOUNT1));
+
+    boolean accelerated = crawler.doPeriodicWork();
+    assertThat(accelerated).isFalse();
+
+    verify(cache, times(1)).claimActiveWork(any(String.class), anyLong());
+    verify(cache, times(dedicatedMigrationCrawler ? 1 : 0)).getLastUuid();
+    verify(cache, times(dedicatedMigrationCrawler ? 0 : 1)).getLastUuidDynamo();
+    if (dedicatedMigrationCrawler) {
+      verify(accounts, times(0)).getAllFrom(eq(CHUNK_SIZE));
+      verify(accounts, times(1)).getAllFrom(eq(ACCOUNT1), eq(CHUNK_SIZE));
+    } else {
+      verify(accounts, times(0)).getAllFromDynamo(eq(CHUNK_SIZE));
+      verify(accounts, times(1)).getAllFromDynamo(eq(ACCOUNT1), eq(CHUNK_SIZE));
+    }
+    verify(listener, times(1)).timeAndProcessCrawlChunk(eq(Optional.of(ACCOUNT1)), eq(Arrays.asList(account2)));
+    verify(cache, times(dedicatedMigrationCrawler ? 1 : 0)).setLastUuid(eq(Optional.of(ACCOUNT2)));
+    verify(cache, times(dedicatedMigrationCrawler ? 0 : 1)).setLastUuidDynamo(eq(Optional.of(ACCOUNT2)));
+    verify(cache, times(1)).isAccelerated();
+    verify(cache, times(1)).releaseActiveWork(any(String.class));
+
+    verifyNoInteractions(account1);
 
     verifyNoMoreInteractions(account2);
     verifyNoMoreInteractions(accounts);