Customized Product Loading In Modify Order

Hi All,

I have one question on product structure loading in modify order creation from external systems. In modify order the request for product A33 has come to add in the structure, how will bundle product A gets loaded.

Will it load entire full structure of each and every component in the back-end and then add A33 product after validating constraints, properties or

Will it not load entire product bundle A, it only check A33 product is available in the structure and validate constraints and then add the component.

1               A

1.1           A1

1.2           A2

1.3           A3

1.3.1       A31

1.3.2       A32

1.3.3       A33

1.3.4       A34  

Thanks in Advance,