Enabling packing slip field on receipt screen to capture it during receipt for fixed price PO lines

Summary:

We are planning to enable packing slip field using form personalization during receipt creation for fixed price PO lines which is currently greyed out. There is a requirement from customer to enable it as they use it for completing receipt matched AP invoice since they have many receipt for same purchase orders.

We want to know if there will be any impact in future if we enable the packing slip field for all types of PO lines including fixed price PO and will the future patches/upgrade applied on the POD will have any issue.

Please confirm and do let us know if there is any better way to acheive the requirement.