diff --git a/uimaj-core/src/main/java/org/apache/uima/cas/impl/FSClassRegistry.java b/uimaj-core/src/main/java/org/apache/uima/cas/impl/FSClassRegistry.java
index 472bdedae..aad9103b8 100644
--- a/uimaj-core/src/main/java/org/apache/uima/cas/impl/FSClassRegistry.java
+++ b/uimaj-core/src/main/java/org/apache/uima/cas/impl/FSClassRegistry.java
@@ -21,6 +21,7 @@
 
 import static java.lang.invoke.MethodHandles.lookup;
 import static java.lang.invoke.MethodType.methodType;
+import static java.util.Collections.emptyMap;
 
 import java.lang.invoke.LambdaMetafactory;
 import java.lang.invoke.MethodHandle;
@@ -393,7 +394,7 @@ private static void loadBuiltins(TypeImpl ti, ClassLoader cl,
 
     if (BuiltinTypeKinds.creatableBuiltinJCas.contains(typeName)
             || typeName.equals(CAS.TYPE_NAME_SOFA)) {
-      JCasClassInfo jcci = getOrCreateJCasClassInfo(ti, cl, type2jcci, defaultLookup);
+      JCasClassInfo jcci = getOrCreateJCasClassInfo(ti, cl, type2jcci, emptyMap());
       assert jcci != null;
       // done while beginning to commit the staticTsi (before committed flag is set), for builtins
       updateOrValidateAllCallSitesForJCasClass(jcci.jcasClass, ti, callSites_toSync);
@@ -481,12 +482,12 @@ private static synchronized void loadJCasForTSandClassLoader(TypeSystemImpl ts,
        */
       // @formatter:on
 
-      ArrayList<MutableCallSite> callSites_toSync = new ArrayList<>();
+      var spiJCasClasses = loadJCasClassesFromSPI(cl);
+      var callSites_toSync = new ArrayList<MutableCallSite>();
       maybeLoadJCasAndSubtypes(ts, ts.topType, type2jcci.get(TOP.class.getCanonicalName()), cl,
-              type2jcci, callSites_toSync);
+              type2jcci, callSites_toSync, spiJCasClasses);
 
-      MutableCallSite[] sync = callSites_toSync
-              .toArray(new MutableCallSite[callSites_toSync.size()]);
+      var sync = callSites_toSync.toArray(new MutableCallSite[callSites_toSync.size()]);
       MutableCallSite.syncAll(sync);
 
       checkConformance(ts, ts.topType, type2jcci);
@@ -531,9 +532,10 @@ private static void setTypeFromJCasIDforBuiltIns(JCasClassInfo jcci, TypeSystemI
   // @formatter:on
   private static void maybeLoadJCasAndSubtypes(TypeSystemImpl tsi, TypeImpl ti,
           JCasClassInfo copyDownDefault_jcasClassInfo, ClassLoader cl,
-          Map<String, JCasClassInfo> type2jcci, ArrayList<MutableCallSite> callSites_toSync) {
+          Map<String, JCasClassInfo> type2jcci, ArrayList<MutableCallSite> callSites_toSync,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
 
-    var jcci = getOrCreateJCasClassInfo(ti, cl, type2jcci, null);
+    var jcci = getOrCreateJCasClassInfo(ti, cl, type2jcci, aSpiJCasClasses);
 
     if (null != jcci && tsi.isCommitted()) {
       updateOrValidateAllCallSitesForJCasClass(jcci.jcasClass, ti, callSites_toSync);
@@ -623,7 +625,8 @@ private static void maybeLoadJCasAndSubtypes(TypeSystemImpl tsi, TypeImpl ti,
     }
 
     for (var subType : ti.getDirectSubtypes()) {
-      maybeLoadJCasAndSubtypes(tsi, subType, jcci_or_copyDown, cl, type2jcci, callSites_toSync);
+      maybeLoadJCasAndSubtypes(tsi, subType, jcci_or_copyDown, cl, type2jcci, callSites_toSync,
+              aSpiJCasClasses);
     }
   }
 
@@ -638,17 +641,36 @@ private static void maybeLoadJCasAndSubtypes(TypeSystemImpl tsi, TypeImpl ti,
    * 
    * @return jcci or null, if no JCas class for this type was able to be loaded
    * 
-   * @deprecated This will become a package private method.
+   * @deprecated This will be removed without replacement
    * @forRemoval 4.0.0
    */
   @Deprecated(since = "3.5.1")
   public static JCasClassInfo getOrCreateJCasClassInfo(TypeImpl aTypeInfo, ClassLoader aClassLoader,
           Map<String, JCasClassInfo> aType2Jcci, Lookup aUnusedLookup) {
 
+    return getOrCreateJCasClassInfo(aTypeInfo, aClassLoader, aType2Jcci,
+            loadJCasClassesFromSPI(aClassLoader));
+  }
+
+  /**
+   * For a particular type name, get the JCasClassInfo
+   * <ul>
+   * <li>by fetching the cached value
+   * <li>by loading the class
+   * <li>return null if no JCas class for this name
+   * </ul>
+   * only called for non-Pear callers
+   * 
+   * @return jcci or null, if no JCas class for this type was able to be loaded
+   */
+  static JCasClassInfo getOrCreateJCasClassInfo(TypeImpl aTypeInfo, ClassLoader aClassLoader,
+          Map<String, JCasClassInfo> aType2Jcci,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
+
     var jcci = aType2Jcci.get(aTypeInfo.getJCasClassName());
 
     if (jcci == null) {
-      jcci = maybeCreateJCasClassInfo(aTypeInfo, aClassLoader, aType2Jcci, aUnusedLookup);
+      jcci = maybeCreateJCasClassInfo(aTypeInfo, aClassLoader, aType2Jcci, aSpiJCasClasses);
     }
 
     // do this setup for new type systems using previously loaded jcci, as well as
@@ -665,10 +687,10 @@ public static JCasClassInfo getOrCreateJCasClassInfo(TypeImpl aTypeInfo, ClassLo
    */
   @Deprecated(since = "3.5.1")
   static JCasClassInfo maybeCreateJCasClassInfo(TypeImpl ti, ClassLoader cl,
-          Map<String, JCasClassInfo> type2jcci, Lookup aUnusedLookup) {
+          Map<String, JCasClassInfo> type2jcci, Map<String, Class<? extends TOP>> aSpiJCasClasses) {
 
     // does update of callsites if was able find JCas class
-    var jcci = createJCasClassInfo(ti, cl, aUnusedLookup);
+    var jcci = createJCasClassInfo(ti, cl, aSpiJCasClasses);
 
     if (null != jcci) {
       type2jcci.put(ti.getJCasClassName(), jcci);
@@ -678,14 +700,19 @@ static JCasClassInfo maybeCreateJCasClassInfo(TypeImpl ti, ClassLoader cl,
   }
 
   /**
-   * @deprecated This will become a private method.
+   * @deprecated This will be removed without replacement.
    * @forRemoval 4.0.0
    */
   @SuppressWarnings("javadoc")
   @Deprecated(since = "3.5.1")
   public static JCasClassInfo createJCasClassInfo(TypeImpl aTypeInfo, ClassLoader aClassLoader,
           Lookup aUnusedLookup) {
-    var jcasClass = maybeJCasWrapperClass(aTypeInfo, aClassLoader);
+    return createJCasClassInfo(aTypeInfo, aClassLoader, loadJCasClassesFromSPI(aClassLoader));
+  }
+
+  private static JCasClassInfo createJCasClassInfo(TypeImpl aTypeInfo, ClassLoader aClassLoader,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
+    var jcasClass = maybeJCasWrapperClass(aTypeInfo, aClassLoader, aSpiJCasClasses);
     if (null == jcasClass || !TOP.class.isAssignableFrom(jcasClass)) {
       return null;
     }
@@ -705,7 +732,6 @@ public static JCasClassInfo createJCasClassInfo(TypeImpl aTypeInfo, ClassLoader
     var lookup = getLookup(jcasClass.getClassLoader());
     return createJCasClassInfo(jcasClass, aTypeInfo, jcasType, lookup);
   }
-
   // static AtomicLong time = IS_TIME_AUGMENT_FEATURES ? new AtomicLong(0) : null;
   //
   // static {
@@ -957,7 +983,8 @@ private static String getAllSuperTypeNames(TypeImpl ti) {
    * @return the loaded / resolved class
    */
   @SuppressWarnings("unchecked")
-  private static Class<? extends TOP> maybeJCasWrapperClass(TypeImpl ti, ClassLoader cl) {
+  private static Class<? extends TOP> maybeJCasWrapperClass(TypeImpl ti, ClassLoader cl,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
     var className = ti.getJCasClassName();
 
     // First we try the local classloader - this is necessary because it might be a PEAR situation
@@ -970,7 +997,7 @@ private static Class<? extends TOP> maybeJCasWrapperClass(TypeImpl ti, ClassLoad
     }
 
     // If the local classloader does not have the JCas wrapper, we try the SPI
-    return loadJCasClassesFromSPI(cl).get(className);
+    return aSpiJCasClasses.get(className);
   }
 
   static Map<String, Class<? extends TOP>> loadJCasClassesFromSPI(ClassLoader cl) {
diff --git a/uimaj-core/src/main/java/org/apache/uima/cas/impl/TypeSystemImpl.java b/uimaj-core/src/main/java/org/apache/uima/cas/impl/TypeSystemImpl.java
index d82cce16c..644184461 100644
--- a/uimaj-core/src/main/java/org/apache/uima/cas/impl/TypeSystemImpl.java
+++ b/uimaj-core/src/main/java/org/apache/uima/cas/impl/TypeSystemImpl.java
@@ -1479,9 +1479,11 @@ private TypeSystemImpl finalizeCommit(ClassLoader cl) {
 
     type2jcci = FSClassRegistry.get_className_to_jcci(cl, false /* is not PEAR */);
     lookup = FSClassRegistry.getLookup(cl);
+    var spiJCasClasses = FSClassRegistry.loadJCasClassesFromSPI(cl);
     cl_for_commit = cl;
 
-    computeAdjustedFeatureOffsets(topType); // must preceed the FSClassRegistry JCas stuff below
+    computeAdjustedFeatureOffsets(topType, spiJCasClasses); // must preceed the FSClassRegistry JCas
+                                                            // stuff below
 
     // Load all the available JCas classes (if not already loaded).
     // Has to follow above, because information computed above is used when
@@ -1529,7 +1531,8 @@ private TypeSystemImpl finalizeCommit(ClassLoader cl) {
    *          - the type
    */
 //@formatter:on
-  private void computeAdjustedFeatureOffsets(TypeImpl ti) {
+  private void computeAdjustedFeatureOffsets(TypeImpl ti,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
 
     List<FeatureImpl> tempIntFis = new ArrayList<>();
     List<FeatureImpl> tempRefFis = new ArrayList<>();
@@ -1549,10 +1552,10 @@ private void computeAdjustedFeatureOffsets(TypeImpl ti) {
     // this includes any superClass of a jcas class which is not in this type system
 
     if (!skip_loading_user_jcas) {
-      JCasClassInfo jcci = getOrCreateJcci(ti);
+      JCasClassInfo jcci = getOrCreateJcci(ti, aSpiJCasClasses);
 
       if (jcci != null) {
-        addJCasOffsetsWithSupers(jcci.jcasClass, tempIntFis, tempRefFis, tempNsr);
+        addJCasOffsetsWithSupers(jcci.jcasClass, tempIntFis, tempRefFis, tempNsr, aSpiJCasClasses);
       }
     }
 
@@ -1582,7 +1585,7 @@ private void computeAdjustedFeatureOffsets(TypeImpl ti) {
     // ti.hasNoSlots = ti.nbrOfUsedIntDataSlots == 0 && ti.nbrOfUsedRefDataSlots == 0;
 
     for (TypeImpl sub : ti.getDirectSubtypes()) {
-      computeAdjustedFeatureOffsets(sub);
+      computeAdjustedFeatureOffsets(sub, aSpiJCasClasses);
     }
   }
 
@@ -1610,7 +1613,8 @@ private void computeAdjustedFeatureOffsets(TypeImpl ti) {
    */
 //@formatter:on
   private void addJCasOffsetsWithSupers(Class<?> clazz, List<FeatureImpl> tempIntFis,
-          List<FeatureImpl> tempRefFis, List<FeatureImpl> tempNsrFis) {
+          List<FeatureImpl> tempRefFis, List<FeatureImpl> tempNsrFis,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
 
     Class<?> superClass = clazz.getSuperclass();
     // **********************
@@ -1634,7 +1638,7 @@ private void addJCasOffsetsWithSupers(Class<?> clazz, List<FeatureImpl> tempIntF
       String uimaTypeName = Misc.javaClassName2UimaTypeName(className);
       TypeImpl ti = getType(uimaTypeName);
       if (ti != null) {
-        maybeAddJCasOffsets(ti, tempIntFis, tempRefFis, tempNsrFis);
+        maybeAddJCasOffsets(ti, tempIntFis, tempRefFis, tempNsrFis, aSpiJCasClasses);
       }
       return;
     }
@@ -1643,7 +1647,7 @@ private void addJCasOffsetsWithSupers(Class<?> clazz, List<FeatureImpl> tempIntF
     // If they exist, they will have been loaded/created by FSClassRegistry.augmentFeaturesFromJCas
     // some intermediate superclasses may not have jccis, just skip over them.
 
-    addJCasOffsetsWithSupers(superClass, tempIntFis, tempRefFis, tempNsrFis);
+    addJCasOffsetsWithSupers(superClass, tempIntFis, tempRefFis, tempNsrFis, aSpiJCasClasses);
     // maybeAddJCasOffsets(clazz, tempIntFis, tempRefFis, tempNsrFis); // already done by above
     // statement
   }
@@ -1661,9 +1665,10 @@ private void addJCasOffsetsWithSupers(Class<?> clazz, List<FeatureImpl> tempIntF
    *          list to augment with additional slots
    */
   private void maybeAddJCasOffsets(TypeImpl ti, List<FeatureImpl> tempIntFis,
-          List<FeatureImpl> tempRefFis, List<FeatureImpl> tempNsrFis) {
+          List<FeatureImpl> tempRefFis, List<FeatureImpl> tempNsrFis,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
 
-    JCasClassInfo jcci = getOrCreateJcci(ti);
+    JCasClassInfo jcci = getOrCreateJcci(ti, aSpiJCasClasses);
     if (null != jcci) { // could be null if class is not a JCas class
       addJCasOffsets(jcci, tempIntFis, tempRefFis, tempNsrFis);
     }
@@ -1735,8 +1740,9 @@ void setOffset2Feat(List<FeatureImpl> tempIntFis, List<FeatureImpl> tempRefFis,
     }
   }
 
-  private JCasClassInfo getOrCreateJcci(TypeImpl ti) {
-    return FSClassRegistry.getOrCreateJCasClassInfo(ti, cl_for_commit, type2jcci, lookup);
+  private JCasClassInfo getOrCreateJcci(TypeImpl ti,
+          Map<String, Class<? extends TOP>> aSpiJCasClasses) {
+    return FSClassRegistry.getOrCreateJCasClassInfo(ti, cl_for_commit, type2jcci, aSpiJCasClasses);
   }
 
   JCasClassInfo getJcci(String typeName) {
diff --git a/uimaj-core/src/test/java/org/apache/uima/cas/impl/TypeSystemImplTest.java b/uimaj-core/src/test/java/org/apache/uima/cas/impl/TypeSystemImplTest.java
index ebb72e14a..a6edee853 100644
--- a/uimaj-core/src/test/java/org/apache/uima/cas/impl/TypeSystemImplTest.java
+++ b/uimaj-core/src/test/java/org/apache/uima/cas/impl/TypeSystemImplTest.java
@@ -18,6 +18,7 @@
  */
 package org.apache.uima.cas.impl;
 
+import static java.lang.System.currentTimeMillis;
 import static org.apache.uima.UIMAFramework.getResourceSpecifierFactory;
 import static org.apache.uima.util.CasCreationUtils.createCas;
 import static org.assertj.core.api.Assertions.assertThat;
@@ -25,6 +26,7 @@
 import static org.assertj.core.api.Assertions.assertThatNoException;
 import static org.assertj.core.api.InstanceOfAssertFactories.throwable;
 
+import java.lang.invoke.MethodHandles;
 import java.lang.management.ManagementFactory;
 
 import org.apache.uima.cas.CAS;
@@ -36,12 +38,16 @@
 import org.apache.uima.resource.metadata.TypeSystemDescription;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import x.y.z.Sentence;
 
 class TypeSystemImplTest {
   private TypeSystemDescription tsd;
 
+  static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
+
   @BeforeEach
   void setup() {
     tsd = getResourceSpecifierFactory().createTypeSystemDescription();
@@ -109,7 +115,16 @@ void testMetaspaceExhaustion() throws Exception {
     var type = tsd.addType(Sentence._TypeName, "", CAS.TYPE_NAME_ANNOTATION);
     type.addFeature(Sentence._FeatName_sentenceLength, null, CAS.TYPE_NAME_INTEGER);
 
+    LOG.info("Metaspace exhaustion test starting - this may take a while...");
+    var startTime = currentTimeMillis();
+    var target = threshold * 2;
     for (var i = 0; i < threshold * 2; i++) {
+      if ((i + 1) % 250 == 0) {
+        var duration = currentTimeMillis() - startTime;
+        LOG.info("Metaspace exhaustion test - progress: {} / {} -- {}ms per CAS", i + 1, target,
+                duration / i + 1);
+      }
+
       var resMgr = new ResourceManager_impl();
       resMgr.setExtensionClassPath(".", false);
       createCas(tsd, null, null, null, resMgr).getJCas();
@@ -121,5 +136,10 @@ void testMetaspaceExhaustion() throws Exception {
               .as("High number of new loaded classes during test indicates leak")
               .isLessThan(classesLoadedAtStart + threshold);
     }
+    LOG.info("Classes accumulated during test: {}",
+            classLoadingMXBean.getLoadedClassCount() - classesLoadedAtStart);
+    var duration = currentTimeMillis() - startTime;
+    LOG.info("Metaspace exhaustion test finished in {}ms ({}ms per CAS)", duration,
+            duration / target);
   }
 }
diff --git a/uimaj-core/src/test/resources/log4j2-test.xml b/uimaj-core/src/test/resources/log4j2-test.xml
index 848041694..1cbdb7ce0 100644
--- a/uimaj-core/src/test/resources/log4j2-test.xml
+++ b/uimaj-core/src/test/resources/log4j2-test.xml
@@ -25,6 +25,8 @@
     </Console>
   </Appenders>
   <Loggers>
+    <Logger name="org.apache.uima.cas.impl.TypeSystemImplTest" level="INFO" />
+  
     <Root level="WARN">
       <AppenderRef ref="Console"/>
     </Root>