diff --git a/private-modules-overrides.yml b/private-modules-overrides.yml
index 1ba04420dcc971edbf840fbc97500b46012e4bef..0d3722c4e1759dc85ea22a6b98861744295ba62a 100644
--- a/private-modules-overrides.yml
+++ b/private-modules-overrides.yml
@@ -1,4 +1,5 @@
 variables:
+  OPT_IN_TEST_PREVIOUS_MAJOR: 1
   OPT_IN_TEST_NEXT_MINOR: 1
   OPT_IN_TEST_NEXT_MAJOR: 0
   RUN_JOB_UPGRADE_STATUS: 0
@@ -27,6 +28,8 @@ phpstan (next major):
   allow_failure: false
   before_script:
     - *provide-info-yml-if-needed
+phpunit (previous major):
+  allow_failure: false
 phpunit (next minor):
   allow_failure: false
 phpunit (next major):