diff --git a/index.php b/index.php
index 95900b1a..5461998c 100644
--- a/index.php
+++ b/index.php
@@ -572,11 +572,9 @@ private function getUpdateServerResponse(): array {
 	 *
 	 * @throws \Exception
 	 */
-	public function downloadUpdate(): void {
+	public function downloadUpdate(?string $url = null): void {
 		$this->silentLog('[info] downloadUpdate()');
 
-		$response = $this->getUpdateServerResponse();
-
 		$storageLocation = $this->getUpdateDirectoryLocation() . '/updater-'.$this->getConfigOptionMandatoryString('instanceid') . '/downloads/';
 		if (file_exists($storageLocation)) {
 			$this->silentLog('[info] storage location exists');
@@ -587,12 +585,26 @@ public function downloadUpdate(): void {
 			throw new \Exception('Could not mkdir storage location');
 		}
 
-		if (!isset($response['url']) || !is_string($response['url'])) {
-			throw new \Exception('Response from update server is missing url');
+		$downloadURL = '';
+		if ($url) {
+			// If a URL is provided, use it directly
+			$downloadURL = $url;
+		} else {
+			// Otherwise, get the download URLs from the update server
+			$response = $this->getUpdateServerResponse();
+
+			if (!isset($response['url']) || !is_string($response['url'])) {
+				throw new \Exception('Response from update server is missing url');
+			}
+			$downloadURL = $response['url'];
+		}
+
+		if (!$downloadURL) {
+			throw new \Exception('No download URL provided or available from update server');
 		}
 
-		$fp = fopen($storageLocation . basename($response['url']), 'w+');
-		$ch = curl_init($response['url']);
+		$fp = fopen($storageLocation . basename($downloadURL), 'w+');
+		$ch = curl_init($downloadURL);
 		curl_setopt_array($ch, [
 			CURLOPT_FILE => $fp,
 			CURLOPT_USERAGENT => 'Nextcloud Updater',
@@ -636,7 +648,7 @@ public function downloadUpdate(): void {
 				$message .= ' - curl error message: ' . $curlErrorMessage;
 			}
 
-			$message .= ' - URL: ' . htmlentities($response['url']);
+			$message .= ' - URL: ' . htmlentities($downloadURL);
 
 			throw new \Exception($message);
 		}
@@ -669,7 +681,7 @@ private function getDownloadedFilePath(): string {
 	 *
 	 * @throws \Exception
 	 */
-	public function verifyIntegrity(): void {
+	public function verifyIntegrity(?string $urlOverride = null): void {
 		$this->silentLog('[info] verifyIntegrity()');
 
 		if ($this->getCurrentReleaseChannel() === 'daily') {
@@ -677,6 +689,11 @@ public function verifyIntegrity(): void {
 			return;
 		}
 
+		if ($urlOverride) {
+			$this->silentLog('[info] custom download url provided, cannot verify signature');
+			return;
+		}
+
 		$response = $this->getUpdateServerResponse();
 		if (empty($response['signature'])) {
 			throw new \Exception('No signature specified for defined update');
diff --git a/lib/UpdateCommand.php b/lib/UpdateCommand.php
index 2c7c75bb..8015e5d8 100644
--- a/lib/UpdateCommand.php
+++ b/lib/UpdateCommand.php
@@ -39,6 +39,7 @@ class UpdateCommand extends Command {
 	protected bool $shouldStop = false;
 	protected bool $skipBackup = false;
 	protected bool $skipUpgrade = false;
+	protected string $urlOverride = '';
 
 	/** @var list<string> strings of text for stages of updater */
 	protected array $checkTexts = [
@@ -63,7 +64,8 @@ protected function configure(): void {
 			->setDescription('Updates the code of an Nextcloud instance')
 			->setHelp("This command fetches the latest code that is announced via the updater server and safely replaces the existing code with the new one.")
 			->addOption('no-backup', null, InputOption::VALUE_NONE, 'Skip backup of current Nextcloud version')
-			->addOption('no-upgrade', null, InputOption::VALUE_NONE, "Don't automatically run occ upgrade");
+			->addOption('no-upgrade', null, InputOption::VALUE_NONE, "Don't automatically run occ upgrade")
+			->addOption('url', null, InputOption::VALUE_OPTIONAL, 'The URL of the Nextcloud release to download');
 	}
 
 	public static function getUpdaterVersion(): string {
@@ -78,6 +80,7 @@ public static function getUpdaterVersion(): string {
 	protected function execute(InputInterface $input, OutputInterface $output) {
 		$this->skipBackup = (bool)$input->getOption('no-backup');
 		$this->skipUpgrade = (bool)$input->getOption('no-upgrade');
+		$this->urlOverride = (string)$input->getOption('url');
 
 		$version = static::getUpdaterVersion();
 		$output->writeln('Nextcloud Updater - version: ' . $version);
@@ -151,7 +154,12 @@ protected function execute(InputInterface $input, OutputInterface $output) {
 		$output->writeln('Current version is ' . $this->updater->getCurrentVersion() . '.');
 
 		// needs to be called that early because otherwise updateAvailable() returns false
-		$updateString = $this->updater->checkForUpdate();
+		if ($this->urlOverride) {
+			$this->updater->log('[info] Using URL override: ' . $this->urlOverride);
+			$updateString = 'Update check forced with URL override: ' . $this->urlOverride;
+		} else {
+			$updateString = $this->updater->checkForUpdate();
+		}
 
 		$output->writeln('');
 
@@ -164,9 +172,11 @@ protected function execute(InputInterface $input, OutputInterface $output) {
 
 		$output->writeln('');
 
-		if (!$this->updater->updateAvailable() && $stepNumber === 0) {
-			$output->writeln('Nothing to do.');
-			return 0;
+		if (!$this->urlOverride) {
+			if (!$this->updater->updateAvailable() && $stepNumber === 0) {
+				$output->writeln('Nothing to do.');
+				return 0;
+			}
 		}
 
 		$questionText = 'Start update';
@@ -378,10 +388,10 @@ protected function executeStep(int $step): array {
 					}
 					break;
 				case 4:
-					$this->updater->downloadUpdate();
+					$this->updater->downloadUpdate($this->urlOverride);
 					break;
 				case 5:
-					$this->updater->verifyIntegrity();
+					$this->updater->verifyIntegrity($this->urlOverride);
 					break;
 				case 6:
 					$this->updater->extractDownload();
diff --git a/lib/Updater.php b/lib/Updater.php
index ea31dca2..f6d3c687 100644
--- a/lib/Updater.php
+++ b/lib/Updater.php
@@ -3,25 +3,8 @@
 declare(strict_types=1);
 
 /**
- * @copyright Copyright (c) 2016-2017 Lukas Reschke <lukas@statuscode.ch>
- * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
- * @copyright Copyright (c) 2018 Jonas Sulzer <jonas@violoncello.ch>
- *
- * @license GNU AGPL version 3 or any later version
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
+ * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
 namespace NC\Updater;
@@ -534,11 +517,9 @@ private function getUpdateServerResponse(): array {
 	 *
 	 * @throws \Exception
 	 */
-	public function downloadUpdate(): void {
+	public function downloadUpdate(?string $url = null): void {
 		$this->silentLog('[info] downloadUpdate()');
 
-		$response = $this->getUpdateServerResponse();
-
 		$storageLocation = $this->getUpdateDirectoryLocation() . '/updater-'.$this->getConfigOptionMandatoryString('instanceid') . '/downloads/';
 		if (file_exists($storageLocation)) {
 			$this->silentLog('[info] storage location exists');
@@ -549,12 +530,26 @@ public function downloadUpdate(): void {
 			throw new \Exception('Could not mkdir storage location');
 		}
 
-		if (!isset($response['url']) || !is_string($response['url'])) {
-			throw new \Exception('Response from update server is missing url');
+		$downloadURL = '';
+		if ($url) {
+			// If a URL is provided, use it directly
+			$downloadURL = $url;
+		} else {
+			// Otherwise, get the download URLs from the update server
+			$response = $this->getUpdateServerResponse();
+
+			if (!isset($response['url']) || !is_string($response['url'])) {
+				throw new \Exception('Response from update server is missing url');
+			}
+			$downloadURL = $response['url'];
+		}
+
+		if (!$downloadURL) {
+			throw new \Exception('No download URL provided or available from update server');
 		}
 
-		$fp = fopen($storageLocation . basename($response['url']), 'w+');
-		$ch = curl_init($response['url']);
+		$fp = fopen($storageLocation . basename($downloadURL), 'w+');
+		$ch = curl_init($downloadURL);
 		curl_setopt_array($ch, [
 			CURLOPT_FILE => $fp,
 			CURLOPT_USERAGENT => 'Nextcloud Updater',
@@ -598,7 +593,7 @@ public function downloadUpdate(): void {
 				$message .= ' - curl error message: ' . $curlErrorMessage;
 			}
 
-			$message .= ' - URL: ' . htmlentities($response['url']);
+			$message .= ' - URL: ' . htmlentities($downloadURL);
 
 			throw new \Exception($message);
 		}
@@ -631,7 +626,7 @@ private function getDownloadedFilePath(): string {
 	 *
 	 * @throws \Exception
 	 */
-	public function verifyIntegrity(): void {
+	public function verifyIntegrity(?string $urlOverride = null): void {
 		$this->silentLog('[info] verifyIntegrity()');
 
 		if ($this->getCurrentReleaseChannel() === 'daily') {
@@ -639,6 +634,11 @@ public function verifyIntegrity(): void {
 			return;
 		}
 
+		if ($urlOverride) {
+			$this->silentLog('[info] custom download url provided, cannot verify signature');
+			return;
+		}
+
 		$response = $this->getUpdateServerResponse();
 		if (empty($response['signature'])) {
 			throw new \Exception('No signature specified for defined update');
diff --git a/updater.phar b/updater.phar
index a652b802..bb10f2fe 100755
Binary files a/updater.phar and b/updater.phar differ
diff --git a/vendor/composer/installed.php b/vendor/composer/installed.php
index 2d4a8348..79f895d6 100644
--- a/vendor/composer/installed.php
+++ b/vendor/composer/installed.php
@@ -3,7 +3,7 @@
         'name' => '__root__',
         'pretty_version' => 'dev-master',
         'version' => 'dev-master',
-        'reference' => '9adb775ee0ca02d832347ddfea2b4c248f2805bc',
+        'reference' => '088152d70d870f9021ea6231578e59d7dbbd6fd0',
         'type' => 'library',
         'install_path' => __DIR__ . '/../../',
         'aliases' => array(),
@@ -13,7 +13,7 @@
         '__root__' => array(
             'pretty_version' => 'dev-master',
             'version' => 'dev-master',
-            'reference' => '9adb775ee0ca02d832347ddfea2b4c248f2805bc',
+            'reference' => '088152d70d870f9021ea6231578e59d7dbbd6fd0',
             'type' => 'library',
             'install_path' => __DIR__ . '/../../',
             'aliases' => array(),
diff --git a/vendor/composer/platform_check.php b/vendor/composer/platform_check.php
index 580fa960..d2225c7d 100644
--- a/vendor/composer/platform_check.php
+++ b/vendor/composer/platform_check.php
@@ -19,8 +19,7 @@
             echo 'Composer detected issues in your platform:' . PHP_EOL.PHP_EOL . str_replace('You are running '.PHP_VERSION.'.', '', implode(PHP_EOL, $issues)) . PHP_EOL.PHP_EOL;
         }
     }
-    trigger_error(
-        'Composer detected issues in your platform: ' . implode(' ', $issues),
-        E_USER_ERROR
+    throw new \RuntimeException(
+        'Composer detected issues in your platform: ' . implode(' ', $issues)
     );
 }