diff --git a/apex/tests/src/java/android/tzdata/mts/TimeZoneVersionTest.java b/apex/tests/src/java/android/tzdata/mts/TimeZoneVersionTest.java
index e25c52e..3b0df26 100644
--- a/apex/tests/src/java/android/tzdata/mts/TimeZoneVersionTest.java
+++ b/apex/tests/src/java/android/tzdata/mts/TimeZoneVersionTest.java
@@ -16,6 +16,7 @@
 package android.tzdata.mts;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 
 import android.icu.util.VersionInfo;
 import android.os.Build;
@@ -44,19 +45,23 @@
     public void timeZoneModuleIsCompatibleWithThisRelease() throws Exception {
         String majorVersion = readMajorFormatVersionFromModuleVersionFile();
         if (Build.VERSION.SDK_INT == Build.VERSION_CODES.Q) {
-
-            // TODO Hack for master: This ain't Q. Remove this after R devices are behaving
+            assertEquals("003", majorVersion);
+        } else if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
+            // TODO Hack for master: This ain't R. Remove this after R devices are behaving
             //  properly.
-            if (VersionInfo.ICU_VERSION.getMajor() > 63) {
+            if (VersionInfo.ICU_VERSION.getMajor() > 66) {
+                // S is 5.x.
+                assertEquals("005", majorVersion);
+            } else {
                 // R is 4.x.
                 assertEquals("004", majorVersion);
-            } else {
-                // Q is 3.x.
-                assertEquals("003", majorVersion);
             }
-        } else if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
-            // R is 4.x.
-            assertEquals("004", majorVersion);
+        } else {
+            // If this fails, a new API level has likely been finalized and can be made
+            // an explicit case. Keep this clause and add an explicit "else if" above.
+            // Consider removing any checks for pre-release devices too if they're not
+            // needed for now.
+            fail("Unhandled SDK_INT version:" + Build.VERSION.SDK_INT);
         }
     }