diff --git a/version/mkversion/mkversion.go b/version/mkversion/mkversion.go
index 49f97be53..7d0a0f5eb 100644
--- a/version/mkversion/mkversion.go
+++ b/version/mkversion/mkversion.go
@@ -291,7 +291,10 @@ func mkOutput(v verInfo) (VersionInfo, error) {
 		// so that we we're still in the same range. This way if Apple goes back to
 		// auto-incrementing the number for us, we can go back to it with
 		// reasonable-looking numbers.
-		ret.XcodeMacOS = fmt.Sprintf("%d.%d.%d", otherTime.Year()-1750, otherTime.YearDay(), otherTime.Hour()*60*60+otherTime.Minute()*60+otherTime.Second())
+		// In May 2024, a build with version number 275 was uploaded to the App Store
+		// by mistake, causing any 274.* build to be rejected. To address this, +1 was
+		// added, causing all builds to use the 275.* prefix.
+		ret.XcodeMacOS = fmt.Sprintf("%d.%d.%d", otherTime.Year()-1750+1, otherTime.YearDay(), otherTime.Hour()*60*60+otherTime.Minute()*60+otherTime.Second())
 	}
 
 	return ret, nil
diff --git a/version/mkversion/mkversion_test.go b/version/mkversion/mkversion_test.go
index 1ae2372b5..210d3053a 100644
--- a/version/mkversion/mkversion_test.go
+++ b/version/mkversion/mkversion_test.go
@@ -81,7 +81,7 @@ func TestMkversion(t *testing.T) {
            VERSION_TRACK="unstable"
            VERSION_EXTRA_HASH="defghi"
            VERSION_XCODE="101.15.129"
-           VERSION_XCODE_MACOS="273.27.3723"
+           VERSION_XCODE_MACOS="274.27.3723"
            VERSION_WINRES="1,15,129,0"
            VERSION_MSIPRODUCT_AMD64="89C96952-1FB8-5A4D-B02E-16A8060C56AA"
            VERSION_MSIPRODUCT_ARM64="DB1A2E86-66C4-5CEC-8F4C-7DB805370F3A"
@@ -104,7 +104,7 @@ func TestMkversion(t *testing.T) {
            VERSION_TRACK="unstable"
            VERSION_EXTRA_HASH="defghi"
            VERSION_XCODE="101.15.129"
-           VERSION_XCODE_MACOS="273.27.3723"
+           VERSION_XCODE_MACOS="274.27.3723"
            VERSION_WINRES="1,15,129,0"
            VERSION_MSIPRODUCT_AMD64="89C96952-1FB8-5A4D-B02E-16A8060C56AA"
            VERSION_MSIPRODUCT_ARM64="DB1A2E86-66C4-5CEC-8F4C-7DB805370F3A"