diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 365ce64ced0ba20c8880f4e4815e36d77873b75c..06afcab3fe6479a3427ad07520f6d7dd07db1bc2 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1567,6 +1567,17 @@ sanitizer-test-osba-hoa3-ism2:
     - *update-ltv-repo
     - python3 ci/run_scheduled_sanitizer_test.py HOA3-ISM2 $OUT_FORMATS_CHANNEL_BASED $OUT_FORMATS_SCENE_BASED $OUT_FORMATS_BINAURAL --tests $SANITIZER_TESTS
 
+sanitizer-test-omasa-ism4:
+  extends: .sanitizer-test-schedule-B
+  rules:
+    - if: $SANITIZER_SCHEDULE_B
+      when: delayed
+      start_in: 97.5 hours
+  timeout: 10 hours
+  script:
+    - *update-ltv-repo
+    - python3 ci/run_scheduled_sanitizer_test.py MASA-ISM4 $OUT_FORMATS_CHANNEL_BASED $OUT_FORMATS_SCENE_BASED $OUT_FORMATS_BINAURAL --tests $SANITIZER_TESTS
+
 
 ### --- sanitizer schedule C ---
 
@@ -1603,22 +1614,12 @@ sanitizer-test-omasa-ism3:
     - *update-ltv-repo
     - python3 ci/run_scheduled_sanitizer_test.py MASA-ISM3 $OUT_FORMATS_CHANNEL_BASED $OUT_FORMATS_SCENE_BASED $OUT_FORMATS_BINAURAL --tests $SANITIZER_TESTS
 
-sanitizer-test-omasa-ism4:
-  extends: .sanitizer-test-schedule-C
-  rules:
-    - if: $SANITIZER_SCHEDULE_C
-      when: delayed
-      start_in: 30 hours
-  script:
-    - *update-ltv-repo
-    - python3 ci/run_scheduled_sanitizer_test.py MASA-ISM4 $OUT_FORMATS_CHANNEL_BASED $OUT_FORMATS_SCENE_BASED $OUT_FORMATS_BINAURAL --tests $SANITIZER_TESTS
-
 sanitizer-test-osba-hoa3-ism3:
   extends: .sanitizer-test-schedule-C
   rules:
     - if: $SANITIZER_SCHEDULE_C
       when: delayed
-      start_in: 40 hours
+      start_in: 30 hours
   timeout: 7.5 hours
   script:
     - *update-ltv-repo
@@ -1629,7 +1630,7 @@ sanitizer-test-osba-hoa3-ism4:
   rules:
     - if: $SANITIZER_SCHEDULE_C
       when: delayed
-      start_in: 47.5 hours
+      start_in: 37.5 hours
   timeout: 7.5 hours
   script:
     - *update-ltv-repo