Hello Sub,
You can see detailed data about change documents in note 180949 - CC-INFO: Change documents during client copy.
The change documents are used by many different applications to log data changes.
Client Copy Profiles are explained in Profiles in the Client Copy.
When you use SAP_ALL profile all data belonging to a client, with the exceptions of change documents and local data, is copied.
This means RFC and BD54 will not be overwritten. But partner profile and BD64 data will be overwritten.
I assume that you will copy PRD system's 400 to QAS systems's 300. Not QAS system's 400 to QAS system's 300.
If so, QAS and PRD system repository are identical then use Remote client copy. Otherwise it will stop giving error. I advise you to use client export and import.
Regards,
Yuksel AKCINAR
