You need to do the same on the routing: go in the routing fucntion and copy the record from the prginal product by entering the new product code (only if same production sites). But you can as well reuse the original routing to the new product (as long as they share the same stick unit) without having to create the routing for the new product. To assign a routing as default for another product you can use the product-site function > Manufacturing tab.

Ok thank you.

Is there a way to automatically renumber the routing lines if you need to add one?

No but this the reason why we use a number with an increment of 10 so you can insert 9 lines before having to chage the line number. By the way you can do it lines per lines using the action menu at the begining of the line 'renumber';

Thank you!