diff --git a/pom.xml b/pom.xml
index da02b78c0..fcd218bee 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>com.uid2</groupId>
     <artifactId>uid2-operator</artifactId>
-    <version>5.66.29</version>
+    <version>5.66.24-alpha-317-SNAPSHOT</version>
   
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
diff --git a/src/main/java/com/uid2/operator/model/MapRequest.java b/src/main/java/com/uid2/operator/model/MapRequest.java
index 1d70c7ba3..afeb2020c 100644
--- a/src/main/java/com/uid2/operator/model/MapRequest.java
+++ b/src/main/java/com/uid2/operator/model/MapRequest.java
@@ -6,13 +6,23 @@ public final class MapRequest {
     public final UserIdentity userIdentity;
     public final Instant asOf;
     public final IdentityEnvironment identityEnvironment;
+    public final boolean includePreviousAdvertisingId;
 
     public MapRequest(
             UserIdentity userIdentity,
             Instant asOf,
             IdentityEnvironment identityEnvironment) {
+        this(userIdentity, asOf, identityEnvironment, true);
+    }
+
+    public MapRequest(
+            UserIdentity userIdentity,
+            Instant asOf,
+            IdentityEnvironment identityEnvironment,
+            boolean includePreviousAdvertisingId) {
         this.userIdentity = userIdentity;
         this.asOf = asOf;
         this.identityEnvironment = identityEnvironment;
+        this.includePreviousAdvertisingId = includePreviousAdvertisingId;
     }
 }
diff --git a/src/main/java/com/uid2/operator/model/MappedIdentity.java b/src/main/java/com/uid2/operator/model/MappedIdentity.java
index df669c171..fd894f3f3 100644
--- a/src/main/java/com/uid2/operator/model/MappedIdentity.java
+++ b/src/main/java/com/uid2/operator/model/MappedIdentity.java
@@ -4,6 +4,13 @@ public class MappedIdentity {
     public static final MappedIdentity LogoutIdentity = new MappedIdentity(new byte[33], "", null, null);
     public final byte[] advertisingId;
     public final String bucketId;
+    /**
+     * The advertising ID computed using the previous rotating salt, or {@code null} if:
+     * <ul>
+     *   <li>The caller did not request it (i.e. {@code MapRequest.includePreviousAdvertisingId} was {@code false}), or</li>
+     *   <li>No previous salt is available, or the salt was last rotated more than 90 days ago.</li>
+     * </ul>
+     */
     public final byte[] previousAdvertisingId;
     public final Long refreshFrom;
 
diff --git a/src/main/java/com/uid2/operator/service/UIDOperatorService.java b/src/main/java/com/uid2/operator/service/UIDOperatorService.java
index 9662dc59d..20531778c 100644
--- a/src/main/java/com/uid2/operator/service/UIDOperatorService.java
+++ b/src/main/java/com/uid2/operator/service/UIDOperatorService.java
@@ -156,7 +156,7 @@ public MappedIdentity mapIdentity(MapRequest request) {
         if (getGlobalOptOutResult(firstLevelHashIdentity, false).isOptedOut()) {
             return MappedIdentity.LogoutIdentity;
         } else {
-            return getMappedIdentity(firstLevelHashIdentity, request.asOf, request.identityEnvironment);
+            return getMappedIdentity(firstLevelHashIdentity, request.asOf, request.identityEnvironment, request.includePreviousAdvertisingId);
         }
     }
 
@@ -248,9 +248,15 @@ private byte[] getFirstLevelHash(byte[] identityHash, Instant asOf) {
     }
 
     private MappedIdentity getMappedIdentity(UserIdentity firstLevelHashIdentity, Instant asOf, IdentityEnvironment env) {
+        return getMappedIdentity(firstLevelHashIdentity, asOf, env, false);
+    }
+
+    private MappedIdentity getMappedIdentity(UserIdentity firstLevelHashIdentity, Instant asOf, IdentityEnvironment env, boolean includePreviousAdvertisingId) {
         final SaltEntry rotatingSalt = getSaltProviderSnapshot(asOf).getRotatingSalt(firstLevelHashIdentity.id);
         final byte[] advertisingId = getAdvertisingId(firstLevelHashIdentity, rotatingSalt.currentSalt(), rotatingSalt.currentKeySalt(), env);
-        final byte[] previousAdvertisingId = getPreviousAdvertisingId(firstLevelHashIdentity, rotatingSalt, asOf, env);
+        final byte[] previousAdvertisingId = includePreviousAdvertisingId
+                ? getPreviousAdvertisingId(firstLevelHashIdentity, rotatingSalt, asOf, env)
+                : null;
         final long refreshFrom = getRefreshFrom(rotatingSalt, asOf);
 
         return new MappedIdentity(
diff --git a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
index 503ac9ace..a4c4ebdac 100644
--- a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
+++ b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
@@ -1114,7 +1114,8 @@ private JsonObject handleIdentityMapCommon(RoutingContext rc, InputUtil.InputVal
                         new MapRequest(
                                 input.toUserIdentity(this.identityScope, 0, now),
                                 now,
-                                env));
+                                env,
+                                false)); // v2 does not use previousAdvertisingId
 
                 if (mappedIdentity.isOptedOut()) {
                     final JsonObject resp = new JsonObject();
diff --git a/src/test/java/com/uid2/operator/UIDOperatorServiceTest.java b/src/test/java/com/uid2/operator/UIDOperatorServiceTest.java
index 8356ffac2..1a572697a 100644
--- a/src/test/java/com/uid2/operator/UIDOperatorServiceTest.java
+++ b/src/test/java/com/uid2/operator/UIDOperatorServiceTest.java
@@ -835,7 +835,7 @@ void testMappedIdentityWithPreviousSaltReturnsPreviousUid() {
 
         var email = "test@uid.com";
         InputUtil.InputVal emailInput = generateInputVal(TestIdentityInputType.Email, email);
-        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now),  now, IdentityEnvironment.TEST);
+        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now), now, IdentityEnvironment.TEST);
 
         MappedIdentity mappedIdentity = uid2Service.mapIdentity(mapRequest);
 
@@ -858,7 +858,7 @@ void testMappedIdentityWithOutdatedPreviousSaltReturnsNoPreviousUid(long extraMs
 
         var email = "test@uid.com";
         InputUtil.InputVal emailInput = generateInputVal(TestIdentityInputType.Email, email);
-        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now),  now, IdentityEnvironment.TEST);
+        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now), now, IdentityEnvironment.TEST);
 
         MappedIdentity mappedIdentity = uid2Service.mapIdentity(mapRequest);
         var expectedCurrentUID = UIDOperatorVerticleTest.getRawUid(IdentityScope.UID2, IdentityType.Email, email, FIRST_LEVEL_SALT, salt.currentSalt(), uid2Config.getBoolean(IdentityV3Prop));
@@ -878,7 +878,7 @@ void testMappedIdentityWithNoPreviousSaltReturnsNoPreviousUid() {
 
         var email = "test@uid.com";
         InputUtil.InputVal emailInput = generateInputVal(TestIdentityInputType.Email, email);
-        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now),  now, IdentityEnvironment.TEST);
+        MapRequest mapRequest = new MapRequest(emailInput.toUserIdentity(IdentityScope.UID2, 0, this.now), now, IdentityEnvironment.TEST);
 
         MappedIdentity mappedIdentity = uid2Service.mapIdentity(mapRequest);