Hey Timo,
Thanks for reaching out and for your interest in our products 🙂
According to this article https://theeventscalendar.com/knowledgebase/using-one-license-live-dev-sites/ my approach should work? Can you confirm this to me? Or am I wrong?
I can confirm your approach will work! Manual updates should work as expected in the testing site.
While we don’t have a trial period, you can go ahead and purchase the products for testing. If you decide they are not what you are looking for, you can ask for a full refund within 30 days of purchase. For more information take a look at our refund policy.
Please let me know if there’s anything else I can help you with,
Best,
Nico