diff --git a/cmd/releasego/update-azure-linux.go b/cmd/releasego/update-azure-linux.go
index 2988955a..2dfe1891 100644
--- a/cmd/releasego/update-azure-linux.go
+++ b/cmd/releasego/update-azure-linux.go
@@ -276,34 +276,20 @@ func updateSpecFile(assets *buildassets.BuildAssets, changelogDate time.Time, sp
 		oldVersion = goversion.New(matches[2])
 	}
 
-	var oldRelease int
+	var oldRelease string
 	if matches := specFileReleaseRegex.FindStringSubmatch(specFileContent); matches == nil {
 		return "", fmt.Errorf("no Release declaration found in spec content")
 	} else {
-		var err error
-		oldRelease, err = strconv.Atoi(matches[2])
-		if err != nil {
-			return "", fmt.Errorf("failed to parse Release number: %w", err)
-		}
+		oldRelease = matches[2]
 	}
 
-	newVersion := assets.GoVersion().MajorMinorPatch()
-	if strings.Contains(newVersion, "$") {
-		return "", fmt.Errorf("new version %q contains unexpected $", newVersion)
-	}
-	specFileContent = specFileVersionRegex.ReplaceAllString(specFileContent, "${1}"+newVersion)
-
-	// For servicing patches, increment release. Azure Linux may have incremented it manually for a
-	// Azure-Linux-specific fix, so this is independent of Microsoft Go releases. When updating to a
-	// new major/minor version (as semver refers to them), reset release to 1.
-	var newRelease int
-	if assets.GoVersion().MajorMinor() != oldVersion.MajorMinor() {
-		newRelease = 1
-	} else {
-		newRelease = oldRelease + 1
+	newVersion, newRelease, err := updateSpecVersion(assets, oldVersion, oldRelease)
+	if err != nil {
+		return "", err
 	}
 
-	specFileContent = specFileReleaseRegex.ReplaceAllString(specFileContent, "${1}"+strconv.Itoa(newRelease)+"${3}")
+	specFileContent = specFileVersionRegex.ReplaceAllString(specFileContent, "${1}"+newVersion)
+	specFileContent = specFileReleaseRegex.ReplaceAllString(specFileContent, "${1}"+newRelease+"${3}")
 	specFileContent = addChangelogToSpecFile(specFileContent, changelogDate, assets)
 
 	return specFileContent, nil
@@ -416,3 +402,31 @@ func updateCGManifest(buildAssets *buildassets.BuildAssets, cgManifestContent []
 
 	return buf.Bytes(), nil
 }
+
+func updateSpecVersion(assets *buildassets.BuildAssets, oldVersion *goversion.GoVersion, oldRelease string) (version, release string, err error) {
+	oldReleaseInt, err := strconv.Atoi(oldRelease)
+	if err != nil {
+		return "", "", fmt.Errorf("failed to parse old Release number: %w", err)
+	}
+
+	newVersion := assets.GoVersion().MajorMinorPatch()
+	if strings.Contains(newVersion, "$") {
+		return "", "", fmt.Errorf("new version %q contains unexpected $", newVersion)
+	}
+
+	// Decide on the new Azure Linux golang package release number.
+	//
+	// We don't use assets.GoVersion().Revision because Azure Linux may have incremented the
+	// release version manually for an Azure-Linux-specific fix.
+	var newRelease int
+	if assets.GoVersion().MajorMinorPatch() != oldVersion.MajorMinorPatch() {
+		// When updating to a new upstream Go version, reset release number to 1.
+		newRelease = 1
+	} else {
+		// When the upstream Go version didn't change, increment the release number. This means
+		// there has been a patch specific to Microsoft Go.
+		newRelease = oldReleaseInt + 1
+	}
+
+	return newVersion, strconv.Itoa(newRelease), nil
+}
diff --git a/cmd/releasego/update-azure-linux_test.go b/cmd/releasego/update-azure-linux_test.go
index 2fc203c7..770addc5 100644
--- a/cmd/releasego/update-azure-linux_test.go
+++ b/cmd/releasego/update-azure-linux_test.go
@@ -10,7 +10,9 @@ import (
 	"testing"
 	"time"
 
+	"github.com/microsoft/go-infra/buildmodel/buildassets"
 	"github.com/microsoft/go-infra/goldentest"
+	"github.com/microsoft/go-infra/goversion"
 )
 
 var assetsJsonPath = filepath.Join("testdata", "update-azure-linux", "assets.json")
@@ -98,3 +100,66 @@ func TestUpdateCGManifestFileContent(t *testing.T) {
 		filepath.Join("testdata", "update-azure-linux", "updated_cgmanifest.golden.json"),
 		string(updatedCgManifestFile))
 }
+
+func TestUpdateSpecVersion(t *testing.T) {
+	type args struct {
+		newGoVersion string
+		oldVersion   string
+		oldRelease   string
+	}
+	tests := []struct {
+		name        string
+		args        args
+		wantVersion string
+		wantRelease string
+		wantErr     bool
+	}{
+		{
+			"patch",
+			args{"1.22.4-1", "1.22.3", "1"},
+			"1.22.4", "1", false,
+		},
+		{
+			"patch-modified-package",
+			args{"1.22.4-1", "1.22.3", "2"},
+			"1.22.4", "1", false,
+		},
+		{
+			"patch-msft-go-release",
+			args{"1.22.3-2", "1.22.3", "1"},
+			"1.22.3", "2", false,
+		},
+		{
+			"patch-msft-go-release-modified",
+			args{"1.22.3-2", "1.22.3", "4"},
+			"1.22.3", "5", false,
+		},
+		{
+			"go-major",
+			args{"1.23.0-1", "1.22.8", "1"},
+			"1.23.0", "1", false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assets := &buildassets.BuildAssets{
+				Version: tt.args.newGoVersion,
+			}
+			gotVersion, gotRelease, err := updateSpecVersion(
+				assets,
+				goversion.New(tt.args.oldVersion),
+				tt.args.oldRelease,
+			)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("updateSpecVersion() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if gotVersion != tt.wantVersion {
+				t.Errorf("updateSpecVersion() gotVersion = %v, want %v", gotVersion, tt.wantVersion)
+			}
+			if gotRelease != tt.wantRelease {
+				t.Errorf("updateSpecVersion() gotRelease = %v, want %v", gotRelease, tt.wantRelease)
+			}
+		})
+	}
+}