Hi,
Purchase order/Service order considered as committed document and send to vendor after final release of Purchase order/Service order with purchasing conditions where only possible for Purchase order/Service order can be outputted as Print by E-Mail.
So your Purchase order/Service order can be printed (with service quantity and price for service per unit with total price etc....) before creation of mentioning of service entry sheet (SES).
After of service entry sheet (SES) created or maintained WRT your Service order, why you and your business want to update your Service order Print again for which service receipted?
Regards,
Biju K