If I classify a service type as "initially pending", in other words: if I want appointments that customers can book for this service approved by my staff before they get confirmed, then it would appear logical to me that a subsequent change of the appointment by the customer would also require approval. But that is not how Amelia operates. What happens, once a pending appointment is confirmed, is that customer can reschedule at his discretion. That is something for you to think about.

The obvious workaround is that you don't give customers for such service types the right to modify/cancel. But that causes other issues. What I have done instead is that I let customers modify/cancel, but set an impossibly long lead time for changing appointments (i.e. 6 months). That works. However, it also means that change requirements that the customer has with regards to his appointment, will now be handled off-line (via email or phone). So still not ideal.

Please note: I don't need your immediate attention on this, as I can live with the workaround. But long-term you may want to change this.