We just released Invition Print & Ship version 1.1.3 for WordPress. This version contains a complete code revision and cleanup for the cronjobs and the callback functions.
The cronjob now works through the WordPress default cron system to comply with the plugin guidelines as preparation for the official release in the plugin directory. The settings for the cronjob have been removed as we noticed a lot of users set their cronjob on a very long timeframe. It’s important to have the latest product stocks in your database to prevent disapointed users, therefore we made the cronjob fixed on every 5 minutes. The cronjob fires when pages are loaded. For small websites this is fine but for larger websites with a lot of visitors you can improve the page speed by disabling the default WordPress cron and create a real cronjob. SiteGround has a nice tutorial for this, Please make sure you set the cronjob for every 5 minutes at least!
The callback script was also completely removed to make sure we meet the guidelines. This is now integrated with an API endpoint in the WordPress REST API. You can test your callback URL by going to:
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