Bootstrap 7.x-3.22 upgrade without Composer and Drush?

I need to upgrade Bootstrap 7.x-3.12 to 7.x-3.22.  Drupal 7.x was not installed with Composer.  I don’t have access to the server to install Drush or Composer.  Without these developer tools, how do I upgrade to the current Bootstrap?  Can I use the Admin UI, Reports > Available Updates > Install New Module or Theme?  Or use ftp to copy unzipped Bootstrap directory on my PC to the server directory /drupal/sites/all/themes/bootstrap/?

Thanks!

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