Please restore ASAP the 50 real orders limit for development stores created before March 30th 2020.
Also the message "This store can't accept real orders or real payments." should not be appearing on the payment page as long as the limit has not been reached yet.
Thanks for providing that context, @SOLIDIDEA. In this case, this is expected. You should have received notification via our Partners Newsletter recently, as well as a notification in your Partners dash. Since development stores are intended to be a testing environment for our partners to create stores before being transferred to merchants for launch, we've changed how orders are processed on dev stores.
You'll still be able to test orders though. Take a look at our documentation on testing orders in development stores here.
Let me know if you have any further questions!