diff --git a/.ci.yaml b/.ci.yaml
index 8eb9a3d13b34..0974ed8c2972 100644
--- a/.ci.yaml
+++ b/.ci.yaml
@@ -85,7 +85,7 @@ platform_properties:
         [
           {"dependency": "ruby", "version": "ruby_3.1-pod_1.13"}
         ]
-      os: "Mac-12|Mac-13"
+      os: "Mac-12"
       device_type: none
       cpu: arm64
       # TODO(vashworth): Remove specific toolchain_ver once https://github.com/flutter/flutter/issues/138109 is resolved.
@@ -101,7 +101,7 @@ platform_properties:
         [
           {"dependency": "ruby", "version": "ruby_3.1-pod_1.13"}
         ]
-      os: "Mac-12|Mac-13"
+      os: "Mac-12"
       device_type: none
       cpu: x86
       # TODO(vashworth): Remove specific toolchain_ver once https://github.com/flutter/flutter/issues/138109 is resolved.