BOL (Bill of Lading) after load complete or after PGI?

Hello EWM experts,

In my project, client will not be using shipment and TU.

Stock will be moved between the plants and the truck carrying the stock will need Bill of Lading (BOL) to accompany it.

Should BOL be printed after Loading or after PGI?

If BOL is printed after Loading -

User need to click the button Load complete on EWM (even if there is no TU).

Enhancement is needed to send stock information (HU number, material qty) on the outbound delivery from EWM to S4 and print BOL.

If BOL is printed after PGI -

No enhancement is needed.

Which is correct design? If both options are correct then, what are advantages and disadvantages in each?

Thank you,

Chaitanya