Our plugin for WooCommerce has an option to choose which scheduler will be used for planning and sending review reminders. The default option is WordPress Cron but you can change it to CR Cron.

If you changed the scheduler to CR Cron, saved settings, and the scheduler was changed back to WordPress Cron, please check if there are any error messages shown at the top of the page.

The most common reason is that no license key was entered on the License Key tab in the settings. A key (Free or Pro) is required for CR Cron to work, so the scheduler is automatically changed back to WordPress Cron when no key is present.