Header Sold to Party Change Inquiry to Quotation to Sales Order

I have the following sequence of sales document

IN > for inquiry

QT> for quotation

OR> for sales order

as per business scenario sold to party can be change at quotation and sales order level, so for the same in b/w copying control I make the following setting

IN to QT (Copying requirement: 002 header Different customer)

QT to OR (Copying requirement: 002 header Different customer)

after above setting, when I create QT quotation with reference to IN inquiry, system open the field of Sold to Party I can change it there.

but when I create OR order with reference to same QT quotation system freeze the sold to party field at sales order level, I want it to be open, just like quotation.

Is there any mistake I am making, please suggest the solution or mistake I am doing.

regards,

Imran khan