diff --git a/.evergreen/generated_configs/tasks.yml b/.evergreen/generated_configs/tasks.yml
index f859169ed..3450e491a 100644
--- a/.evergreen/generated_configs/tasks.yml
+++ b/.evergreen/generated_configs/tasks.yml
@@ -805,7 +805,7 @@ tasks:
           SUB_TEST_NAME: azure-fail
 
   # Load balancer tests
-  - name: test-load-balancer-auth-ssl
+  - name: test-load-balancer-auth-ssl-v6.0
     commands:
       - func: run server
         vars:
@@ -813,13 +813,74 @@ tasks:
           AUTH: auth
           SSL: ssl
           TEST_NAME: load_balancer
+          VERSION: "6.0"
       - func: run tests
         vars:
           AUTH: auth
           SSL: ssl
           TEST_NAME: load_balancer
     tags: [load-balancer, auth, ssl]
-  - name: test-load-balancer-noauth-ssl
+  - name: test-load-balancer-auth-ssl-v7.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: "7.0"
+      - func: run tests
+        vars:
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, auth, ssl]
+  - name: test-load-balancer-auth-ssl-v8.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: "8.0"
+      - func: run tests
+        vars:
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, auth, ssl]
+  - name: test-load-balancer-auth-ssl-rapid
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: rapid
+      - func: run tests
+        vars:
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, auth, ssl]
+  - name: test-load-balancer-auth-ssl-latest
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: latest
+      - func: run tests
+        vars:
+          AUTH: auth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, auth, ssl]
+  - name: test-load-balancer-noauth-ssl-v6.0
     commands:
       - func: run server
         vars:
@@ -827,13 +888,74 @@ tasks:
           AUTH: noauth
           SSL: ssl
           TEST_NAME: load_balancer
+          VERSION: "6.0"
       - func: run tests
         vars:
           AUTH: noauth
           SSL: ssl
           TEST_NAME: load_balancer
     tags: [load-balancer, noauth, ssl]
-  - name: test-load-balancer-noauth-nossl
+  - name: test-load-balancer-noauth-ssl-v7.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: "7.0"
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, ssl]
+  - name: test-load-balancer-noauth-ssl-v8.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: "8.0"
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, ssl]
+  - name: test-load-balancer-noauth-ssl-rapid
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: rapid
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, ssl]
+  - name: test-load-balancer-noauth-ssl-latest
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+          VERSION: latest
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: ssl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, ssl]
+  - name: test-load-balancer-noauth-nossl-v6.0
     commands:
       - func: run server
         vars:
@@ -841,6 +963,67 @@ tasks:
           AUTH: noauth
           SSL: nossl
           TEST_NAME: load_balancer
+          VERSION: "6.0"
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, nossl]
+  - name: test-load-balancer-noauth-nossl-v7.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+          VERSION: "7.0"
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, nossl]
+  - name: test-load-balancer-noauth-nossl-v8.0
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+          VERSION: "8.0"
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, nossl]
+  - name: test-load-balancer-noauth-nossl-rapid
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+          VERSION: rapid
+      - func: run tests
+        vars:
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+    tags: [load-balancer, noauth, nossl]
+  - name: test-load-balancer-noauth-nossl-latest
+    commands:
+      - func: run server
+        vars:
+          TOPOLOGY: sharded_cluster
+          AUTH: noauth
+          SSL: nossl
+          TEST_NAME: load_balancer
+          VERSION: latest
       - func: run tests
         vars:
           AUTH: noauth
diff --git a/.evergreen/generated_configs/variants.yml b/.evergreen/generated_configs/variants.yml
index 2242e9c33..9d299fc7f 100644
--- a/.evergreen/generated_configs/variants.yml
+++ b/.evergreen/generated_configs/variants.yml
@@ -599,56 +599,13 @@ buildvariants:
       PYTHON_BINARY: /opt/python/3.13/bin/python3
 
   # Load balancer tests
-  - name: load-balancer-rhel8-v6.0-python3.9
+  - name: load-balancer
     tasks:
       - name: .load-balancer
-    display_name: Load Balancer RHEL8 v6.0 Python3.9
+    display_name: Load Balancer
     run_on:
       - rhel87-small
     batchtime: 10080
-    expansions:
-      VERSION: "6.0"
-      PYTHON_BINARY: /opt/python/3.9/bin/python3
-  - name: load-balancer-rhel8-v7.0-python3.9
-    tasks:
-      - name: .load-balancer
-    display_name: Load Balancer RHEL8 v7.0 Python3.9
-    run_on:
-      - rhel87-small
-    batchtime: 10080
-    expansions:
-      VERSION: "7.0"
-      PYTHON_BINARY: /opt/python/3.9/bin/python3
-  - name: load-balancer-rhel8-v8.0-python3.9
-    tasks:
-      - name: .load-balancer
-    display_name: Load Balancer RHEL8 v8.0 Python3.9
-    run_on:
-      - rhel87-small
-    batchtime: 10080
-    expansions:
-      VERSION: "8.0"
-      PYTHON_BINARY: /opt/python/3.9/bin/python3
-  - name: load-balancer-rhel8-rapid-python3.9
-    tasks:
-      - name: .load-balancer
-    display_name: Load Balancer RHEL8 rapid Python3.9
-    run_on:
-      - rhel87-small
-    batchtime: 10080
-    expansions:
-      VERSION: rapid
-      PYTHON_BINARY: /opt/python/3.9/bin/python3
-  - name: load-balancer-rhel8-latest-python3.9
-    tasks:
-      - name: .load-balancer
-    display_name: Load Balancer RHEL8 latest Python3.9
-    run_on:
-      - rhel87-small
-    batchtime: 10080
-    expansions:
-      VERSION: latest
-      PYTHON_BINARY: /opt/python/3.9/bin/python3
 
   # Mockupdb tests
   - name: mockupdb-rhel8-python3.9
diff --git a/.evergreen/scripts/generate_config.py b/.evergreen/scripts/generate_config.py
index 24aadfbe0..ca8146460 100644
--- a/.evergreen/scripts/generate_config.py
+++ b/.evergreen/scripts/generate_config.py
@@ -413,23 +413,11 @@ def create_encryption_variants() -> list[BuildVariant]:
 
 def create_load_balancer_variants():
     # Load balancer tests - run all supported server versions using the lowest supported python.
-    host = DEFAULT_HOST
-    batchtime = BATCHTIME_WEEK
-    versions = get_versions_from("6.0")
-    variants = []
-    for version in versions:
-        python = CPYTHONS[0]
-        display_name = get_variant_name("Load Balancer", host, python=python, version=version)
-        variant = create_variant(
-            [".load-balancer"],
-            display_name,
-            python=python,
-            host=host,
-            version=version,
-            batchtime=batchtime,
+    return [
+        create_variant(
+            [".load-balancer"], "Load Balancer", host=DEFAULT_HOST, batchtime=BATCHTIME_WEEK
         )
-        variants.append(variant)
-    return variants
+    ]
 
 
 def create_compression_variants():
@@ -830,11 +818,15 @@ def create_server_tasks():
 
 def create_load_balancer_tasks():
     tasks = []
-    for auth, ssl in AUTH_SSLS:
-        name = f"test-load-balancer-{auth}-{ssl}".lower()
+    for (auth, ssl), version in product(AUTH_SSLS, get_versions_from("6.0")):
+        name = get_task_name(f"test-load-balancer-{auth}-{ssl}", version=version)
         tags = ["load-balancer", auth, ssl]
         server_vars = dict(
-            TOPOLOGY="sharded_cluster", AUTH=auth, SSL=ssl, TEST_NAME="load_balancer"
+            TOPOLOGY="sharded_cluster",
+            AUTH=auth,
+            SSL=ssl,
+            TEST_NAME="load_balancer",
+            VERSION=version,
         )
         server_func = FunctionCall(func="run server", vars=server_vars)
         test_vars = dict(AUTH=auth, SSL=ssl, TEST_NAME="load_balancer")
diff --git a/test/retryable_reads/unified/estimatedDocumentCount.json b/test/retryable_reads/unified/estimatedDocumentCount.json
index 75a676b9b..2ee29f679 100644
--- a/test/retryable_reads/unified/estimatedDocumentCount.json
+++ b/test/retryable_reads/unified/estimatedDocumentCount.json
@@ -195,7 +195,7 @@
           "object": "collection1",
           "name": "estimatedDocumentCount",
           "expectError": {
-            "isError": true
+            "isClientError": true
           }
         }
       ],
@@ -241,7 +241,7 @@
           "object": "collection0",
           "name": "estimatedDocumentCount",
           "expectError": {
-            "isError": true
+            "isClientError": true
           }
         }
       ],
diff --git a/test/unified-test-format/valid-pass/expectedError-isClientError.json b/test/unified-test-format/valid-pass/expectedError-isClientError.json
new file mode 100644
index 000000000..9c6beda58
--- /dev/null
+++ b/test/unified-test-format/valid-pass/expectedError-isClientError.json
@@ -0,0 +1,74 @@
+{
+  "description": "expectedError-isClientError",
+  "schemaVersion": "1.3",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.0",
+      "topologies": [
+        "single",
+        "replicaset"
+      ]
+    },
+    {
+      "minServerVersion": "4.1.7",
+      "topologies": [
+        "sharded",
+        "load-balanced"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": false
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "test"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "isClientError considers network errors",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "ping"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "runCommand",
+          "object": "database0",
+          "arguments": {
+            "commandName": "ping",
+            "command": {
+              "ping": 1
+            }
+          },
+          "expectError": {
+            "isClientError": true
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/test/unified-test-format/valid-pass/operation-empty_array.json b/test/unified-test-format/valid-pass/operation-empty_array.json
new file mode 100644
index 000000000..93b25c983
--- /dev/null
+++ b/test/unified-test-format/valid-pass/operation-empty_array.json
@@ -0,0 +1,10 @@
+{
+  "description": "operation-empty_array",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "Empty operations array",
+      "operations": []
+    }
+  ]
+}