diff --git a/tests/e2e/specs/general-settings-invalid-timezone.test.js b/tests/e2e/specs/general-settings-invalid-timezone.test.js
index 9dca6306a4767..5e3fd653066a9 100644
--- a/tests/e2e/specs/general-settings-invalid-timezone.test.js
+++ b/tests/e2e/specs/general-settings-invalid-timezone.test.js
@@ -1,17 +1,59 @@
+import { execFileSync } from 'node:child_process';
+import { join } from 'node:path';
 import { test, expect } from '@wordpress/e2e-test-utils-playwright';
 
+function timezoneOptions( baseURL, values ) {
+	const restore = values === undefined ? '' : `
+		$values = json_decode( base64_decode( '${ Buffer.from( JSON.stringify( values ) ).toString( 'base64' ) }' ), true );
+		foreach ( $values as $option => $value ) {
+			update_option( $option, $value );
+		}
+	`;
+
+	return JSON.parse( execFileSync( process.execPath, [
+		join( process.cwd(), 'tools/local-env/scripts/docker.js' ),
+		'exec', '--user', 'wp_php', 'cli', 'wp', `--url=${ baseURL }`, 'eval',
+		`
+			// Read and restore the stored offset, not the value calculated for a named timezone.
+			remove_filter( 'pre_option_gmt_offset', 'wp_timezone_override_offset' );
+			${ restore }
+			echo wp_json_encode( array(
+				'timezone_string' => get_option( 'timezone_string' ),
+				'gmt_offset' => get_option( 'gmt_offset' ),
+			) );
+		`,
+	], { encoding: 'utf-8', env: { ...process.env, DOTENV_CONFIG_QUIET: 'true' } } ) );
+}
+
 test.describe( 'Settings -> General', () => {
 	const invalidTimezones = [ '', '0', 'Barry/Gary' ];
+	let originalOptions;
+
+	test.beforeEach( async ( { admin, baseURL } ) => {
+		originalOptions = undefined;
+		originalOptions = timezoneOptions( baseURL );
+		await admin.visitAdminPage( '/options-general.php' );
+	} );
+
+	test.afterEach( async ( { baseURL } ) => {
+		if ( originalOptions === undefined ) {
+			return;
+		}
+
+		// The settings form can normalize stored UTC offsets, so restore the options directly.
+		expect( timezoneOptions( baseURL, originalOptions ) ).toEqual( originalOptions );
+	} );
 
 	for ( const invalidTimezone of invalidTimezones ) {
 		test( `Does not allow saving an invalid timezone string with "${invalidTimezone}"`, async ( { admin, page } ) => {
-			await admin.visitAdminPage( '/options-general.php' );
+			const validTimezone = originalOptions.timezone_string === 'Europe/Lisbon' ? 'Africa/Libreville' : 'Europe/Lisbon';
 
-			// Set the timezone to a valid value.
-			await page.locator( '#timezone_string' ).evaluate( timezone => timezone.value = 'Europe/Lisbon' );
+			// Set the timezone to a different valid value.
+			await page.locator( '#timezone_string' ).selectOption( validTimezone );
 
 			// Save changes.
 			await page.locator( '#submit' ).click();
+			await expect( page.locator( '#setting-error-settings_updated' ) ).toContainText( 'Settings saved.' );
 
 			// Set the timezone to an invalid value.
 			await page.locator( '#timezone_string' ).evaluate( ( timezone, invalidTimezone ) => {
@@ -22,7 +64,12 @@ test.describe( 'Settings -> General', () => {
 			// Save changes.
 			await page.locator( '#submit' ).click();
 
-			await expect( page.locator( '#timezone_string' ) ).toHaveValue( 'Europe/Lisbon' );
+			await expect( page.locator( '#setting-error-settings_updated' ) ).toContainText( 'The timezone you have entered is not valid. Please select a valid timezone.' );
+			await expect( page.locator( '#timezone_string' ) ).toHaveValue( validTimezone );
+
+			// Verify the saved value on a fresh page, not just the submit response.
+			await admin.visitAdminPage( '/options-general.php' );
+			await expect( page.locator( '#timezone_string' ) ).toHaveValue( validTimezone );
 		} );
 	}
 } );