The Quick RMA Entry screen enables the creation of new RMA records and review of existing records. The screen can be found here:

System Management > Automation Management > Material Management > Shipping / Receiving > General Operations

The only header data that can be modified after it has been created is the Return Date, comment and process checkboxes.

While, details can be deleted and modified using the detail tab.

Once the record has been successfully processed any changes to the this record will not apply to the created RMA, DMRs and credit notes.