You can now delete appointment types from Cliniko that you no longer need. All previous appointments of that type will not be affected. Previously you could only delete appointment types that hadn't been used yet.
A warning has also been added to the edit page of appointment types advising that changes to the appointment type name will affect all previous appointments. If you want to add a new appointment type, the recommended approach is to create a new one and delete the old one (not rename it).