diff --git a/.ci.yaml b/.ci.yaml
index 2cb1a4b..2febae5 100644
--- a/.ci.yaml
+++ b/.ci.yaml
@@ -53,7 +53,7 @@
         ]
       device_type: none
       cpu: x86
-      os: Mac-12|Mac-13
+      os: Mac-12
       # TODO(vashworth): Remove specific toolchain_ver once https://github.com/flutter/flutter/issues/138109 is resolved.
       $flutter/osx_sdk : >-
         {
@@ -458,7 +458,7 @@
           "toolchain_ver_intel": "Zp2HmSx7_-pu-yHqYqzoEpo0JRwNZGGwSj5V1SnLFmoC"
         }
     drone_dimensions:
-      - os=Mac-12|Mac-13
+      - os=Mac-12
 
   - name: Linux mac_unopt
     recipe: engine_v2/engine_v2
@@ -482,7 +482,7 @@
           "toolchain_ver_intel": "Zp2HmSx7_-pu-yHqYqzoEpo0JRwNZGGwSj5V1SnLFmoC"
         }
     drone_dimensions:
-      - os=Mac-12|Mac-13
+      - os=Mac-12
       - cpu=x86
 
   - name: Mac impeller-cmake-example
diff --git a/ci/builders/mac_android_aot_engine.json b/ci/builders/mac_android_aot_engine.json
index 5704a2b..181cc38 100644
--- a/ci/builders/mac_android_aot_engine.json
+++ b/ci/builders/mac_android_aot_engine.json
@@ -14,7 +14,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -55,7 +55,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -97,7 +97,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -139,7 +139,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -180,7 +180,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -222,7 +222,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
diff --git a/ci/builders/mac_clang_tidy.json b/ci/builders/mac_clang_tidy.json
index 4e3fe0c..f68aa40 100644
--- a/ci/builders/mac_clang_tidy.json
+++ b/ci/builders/mac_clang_tidy.json
@@ -3,7 +3,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -24,7 +24,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -50,7 +50,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -82,7 +82,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -114,7 +114,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -146,7 +146,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -178,7 +178,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
diff --git a/ci/builders/mac_clang_tidy_presubmit.json b/ci/builders/mac_clang_tidy_presubmit.json
index 50deb4c..19f0304 100644
--- a/ci/builders/mac_clang_tidy_presubmit.json
+++ b/ci/builders/mac_clang_tidy_presubmit.json
@@ -3,7 +3,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -24,7 +24,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -50,7 +50,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -82,7 +82,7 @@
             "recipe": "engine_v2/tester_engine",
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
diff --git a/ci/builders/mac_host_engine.json b/ci/builders/mac_host_engine.json
index c00f8a5..4f2fad7 100644
--- a/ci/builders/mac_host_engine.json
+++ b/ci/builders/mac_host_engine.json
@@ -15,7 +15,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86",
                 "mac_model=Macmini8,1"
             ],
@@ -81,7 +81,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86",
                 "mac_model=Macmini8,1"
             ],
@@ -143,7 +143,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86",
                 "mac_model=Macmini8,1"
             ],
@@ -214,7 +214,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -263,7 +263,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -309,7 +309,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
diff --git a/ci/builders/mac_impeller_cmake_example.json b/ci/builders/mac_impeller_cmake_example.json
index 291a4a2..5a9596d 100644
--- a/ci/builders/mac_impeller_cmake_example.json
+++ b/ci/builders/mac_impeller_cmake_example.json
@@ -5,7 +5,7 @@
             "archives": [],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
diff --git a/ci/builders/mac_ios_engine.json b/ci/builders/mac_ios_engine.json
index 67d43aa..cb18b23 100644
--- a/ci/builders/mac_ios_engine.json
+++ b/ci/builders/mac_ios_engine.json
@@ -3,7 +3,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -28,7 +28,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -54,7 +54,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -80,7 +80,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -107,7 +107,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -134,7 +134,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -160,7 +160,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -187,7 +187,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -214,7 +214,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
@@ -242,7 +242,7 @@
         {
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gn": [
diff --git a/ci/builders/mac_unopt.json b/ci/builders/mac_unopt.json
index 74aec4e..866b882 100644
--- a/ci/builders/mac_unopt.json
+++ b/ci/builders/mac_unopt.json
@@ -11,7 +11,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86",
                 "mac_model=Macmini8,1"
             ],
@@ -75,7 +75,7 @@
             },
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=x86"
             ],
             "gclient_variables": {
@@ -132,7 +132,7 @@
             ],
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -185,7 +185,7 @@
             },
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {
@@ -257,7 +257,7 @@
             },
             "drone_dimensions": [
                 "device_type=none",
-                "os=Mac-12|Mac-13",
+                "os=Mac-12",
                 "cpu=arm64"
             ],
             "gclient_variables": {