diff --git a/actions/release-tag-creation/current-version-validation.test.ts b/actions/release-tag-creation/current-version-validation.test.ts
index 4b03436b3..362ffdcad 100644
--- a/actions/release-tag-creation/current-version-validation.test.ts
+++ b/actions/release-tag-creation/current-version-validation.test.ts
@@ -59,9 +59,16 @@ describe('checkVersionIsNext', () => {
 			['4.2.0-beta1', '4.2.0-beta2'],
 			'4.2.0-beta2',
 			false,
-			'Expected next beta to be 4.2.0-beta3',
+			'must be greater than the latest beta tag 4.2.0-beta2',
+		],
+		[
+			'beta',
+			['4.2.0-beta1', '4.2.0-beta2'],
+			'4.2.0-beta1',
+			false,
+			'must be greater than the latest beta tag 4.2.0-beta2',
 		],
-		// beta — next minor / next major
+		// beta — new version line (must be greater than latest AND beta1)
 		['beta', ['4.2.0-beta1', '4.2.0-beta2'], '4.3.0-beta1', true, null],
 		['beta', ['4.2.0-beta1', '4.2.0-beta2'], '5.0.0-beta1', true, null],
 		[
@@ -99,6 +106,14 @@ describe('checkVersionIsNext', () => {
 			false,
 			'Expected next beta line to be 4.3.0-beta1 or 5.0.0-beta1',
 		],
+		// beta — older version line must be rejected (regression)
+		[
+			'beta',
+			['4.2.0-beta1', '4.2.0-beta2'],
+			'4.1.0-beta1',
+			false,
+			'must be greater than the latest beta tag 4.2.0-beta2',
+		],
 		// beta — no existing tags
 		['beta', ['4.1.0', '4.2.0'], '4.2.0-beta1', true, null],
 	] as const)(
diff --git a/actions/release-tag-creation/current-version-validation.ts b/actions/release-tag-creation/current-version-validation.ts
index dff2f9b4b..114a14ac5 100644
--- a/actions/release-tag-creation/current-version-validation.ts
+++ b/actions/release-tag-creation/current-version-validation.ts
@@ -48,6 +48,12 @@ function validateNextBeta(
 	l: semver.SemVer,
 	latest: string,
 ): void {
+	if (!semver.gt(n, l)) {
+		throw new Error(
+			`Version ${version} must be greater than the latest beta tag ${latest}.`,
+		);
+	}
+
 	const latestBetaNum = Number(String(l.prerelease[0]).replace('beta', ''));
 	const newBetaNum = Number(String(n.prerelease[0]).replace('beta', ''));
 	const sameLine =