diff --git a/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php b/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
index 6d27adfa7a2a952898414e7179763399b465bd5c..6f694e6180a739ae052548e6db7cdf9ef47bd542 100644
--- a/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
+++ b/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
@@ -59,8 +59,7 @@ abstract class AutomaticUpdatesFunctionalTestBase extends BrowserTestBase {
       ];
     }
     file_put_contents($services_file, Yaml::encode($services));
-    // Ensure the container is rebuilt ASAP.
-    $this->kernel->invalidateContainer();
+    $this->rebuildContainer();
   }
 
   /**
diff --git a/tests/src/Functional/ReadinessValidationTest.php b/tests/src/Functional/ReadinessValidationTest.php
index ef9890e0208376f7621890d621516707efc09d10..734012dca74502d825dd02fbb70001d1fa9703a9 100644
--- a/tests/src/Functional/ReadinessValidationTest.php
+++ b/tests/src/Functional/ReadinessValidationTest.php
@@ -373,11 +373,6 @@ class ReadinessValidationTest extends AutomaticUpdatesFunctionalTestBase {
    * Tests that stored validation results are deleted after an update.
    */
   public function testStoredResultsClearedAfterUpdate(): void {
-    // Because all actual staging operations are bypassed by
-    // package_manager_bypass, disable this validator because it will complain
-    // if there's no actual Composer data to inspect.
-    $this->disableValidators(['automatic_updates.staged_projects_validator']);
-
     $assert_session = $this->assertSession();
     $page = $this->getSession()->getPage();
     $this->drupalLogin($this->checkerRunnerUser);
@@ -396,6 +391,10 @@ class ReadinessValidationTest extends AutomaticUpdatesFunctionalTestBase {
       'automatic_updates_test',
       'package_manager_bypass',
     ]);
+    // Because all actual staging operations are bypassed by
+    // package_manager_bypass, disable this validator because it will complain
+    // if there's no actual Composer data to inspect.
+    $this->disableValidators(['automatic_updates.staged_projects_validator']);
 
     // The error should be persistently visible, even after the checker stops
     // flagging it.