diff --git a/RELEASE-NOTES-1.35 b/RELEASE-NOTES-1.35
index 280e6de04c0..1de7d58963a 100644
--- a/RELEASE-NOTES-1.35
+++ b/RELEASE-NOTES-1.35
@@ -644,6 +644,9 @@ because of Phabricator reports.
     - AuthenticationProvider
     - ResourceLoaderModule
     - SearchEngine
+* The parameters to ChronologyProtector::getTouched() and
+  ILBFactory::getChronologyProtectorTouched() were changed without backwards
+  compatibility.
 * …
 
 === Deprecations in 1.35 ===
diff --git a/includes/libs/rdbms/ChronologyProtector.php b/includes/libs/rdbms/ChronologyProtector.php
index 35c12ea61ba..d85804c6e15 100644
--- a/includes/libs/rdbms/ChronologyProtector.php
+++ b/includes/libs/rdbms/ChronologyProtector.php
@@ -35,6 +35,8 @@ use Wikimedia\WaitConditionLoop;
  * This helps to ensure a consistent ordering of events as seen by an client
  *
  * Kind of like Hawking's [[Chronology Protection Agency]].
+ *
+ * @internal
  */
 class ChronologyProtector implements LoggerAwareInterface {
 	/** @var BagOStuff */
@@ -269,21 +271,23 @@ class ChronologyProtector implements LoggerAwareInterface {
 	}
 
 	/**
-	 * @param string $dbName DB master name (e.g. "db1052")
+	 * @param ILoadBalancer $lb The load balancer. Prior to 1.35, the first parameter was the
+	 *   master name.
 	 * @return float|bool UNIX timestamp when client last touched the DB; false if not on record
-	 * @since 1.28
+	 * @since 1.35
 	 */
-	public function getTouched( $dbName ) {
-		return $this->store->get( $this->getTouchedKey( $this->store, $dbName ) );
+	public function getTouched( ILoadBalancer $lb ) {
+		$masterName = $lb->getServerName( $lb->getWriterIndex() );
+		return $this->store->get( $this->getTouchedKey( $this->store, $masterName ) );
 	}
 
 	/**
 	 * @param BagOStuff $store
-	 * @param string $dbName
+	 * @param string $masterName
 	 * @return string
 	 */
-	private function getTouchedKey( BagOStuff $store, $dbName ) {
-		return $store->makeGlobalKey( __CLASS__, 'mtime', $this->clientId, $dbName );
+	private function getTouchedKey( BagOStuff $store, $masterName ) {
+		return $store->makeGlobalKey( __CLASS__, 'mtime', $this->clientId, $masterName );
 	}
 
 	/**
diff --git a/includes/libs/rdbms/lbfactory/ILBFactory.php b/includes/libs/rdbms/lbfactory/ILBFactory.php
index 47d1540f846..92af3d6a078 100644
--- a/includes/libs/rdbms/lbfactory/ILBFactory.php
+++ b/includes/libs/rdbms/lbfactory/ILBFactory.php
@@ -330,10 +330,10 @@ interface ILBFactory {
 	public function commitAndWaitForReplication( $fname, $ticket, array $opts = [] );
 
 	/**
-	 * @param string $dbName DB master name (e.g. "db1052")
+	 * @param DatabaseDomain|string|bool $domain Domain ID, or false for the current domain
 	 * @return float|bool UNIX timestamp when client last touched the DB or false if not recent
 	 */
-	public function getChronologyProtectorTouched( $dbName );
+	public function getChronologyProtectorTouched( $domain = false );
 
 	/**
 	 * Disable the ChronologyProtector for all load balancers
diff --git a/includes/libs/rdbms/lbfactory/LBFactory.php b/includes/libs/rdbms/lbfactory/LBFactory.php
index a4f252220d5..ff9542c5aea 100644
--- a/includes/libs/rdbms/lbfactory/LBFactory.php
+++ b/includes/libs/rdbms/lbfactory/LBFactory.php
@@ -530,8 +530,8 @@ abstract class LBFactory implements ILBFactory {
 		return $waitSucceeded;
 	}
 
-	public function getChronologyProtectorTouched( $dbName ) {
-		return $this->getChronologyProtector()->getTouched( $dbName );
+	public function getChronologyProtectorTouched( $domain = false ) {
+		return $this->getChronologyProtector()->getTouched( $this->getMainLB( $domain ) );
 	}
 
 	public function disableChronologyProtection() {
diff --git a/tests/phpunit/includes/db/LBFactoryTest.php b/tests/phpunit/includes/db/LBFactoryTest.php
index 17034102f85..b15318c8fb4 100644
--- a/tests/phpunit/includes/db/LBFactoryTest.php
+++ b/tests/phpunit/includes/db/LBFactoryTest.php
@@ -799,4 +799,21 @@ class LBFactoryTest extends MediaWikiTestCase {
 		$this->assertEquals( 'realdb', $lb->resolveDomainID( 'alias-db' ) );
 		$this->assertEquals( "realdb-realprefix_", $lb->resolveDomainID( "alias-db-prefix_" ) );
 	}
+
+	/**
+	 * @covers \Wikimedia\Rdbms\ChronologyProtector
+	 * @covers \Wikimedia\Rdbms\LBFactory
+	 */
+	public function testGetChronologyProtectorTouched() {
+		$store = new HashBagOStuff;
+		$lbFactory = $this->newLBFactoryMulti( [
+			'memStash' => $store
+		] );
+		$lbFactory->setRequestInfo( [ 'ChronologyClientId' => 'ii' ] );
+		$key = $store->makeGlobalKey( ChronologyProtector::class,
+			'mtime', 'ii', 'test-db1' );
+		$store->set( $key, 2 );
+		$touched = $lbFactory->getChronologyProtectorTouched();
+		$this->assertEquals( 2, $touched );
+	}
 }