Planned production orders: update procedure

Hi all,

I have a question about planned production order. When I create a new production order in Baan IV sometimes it automatically updates when I change the bom of the article of the production order.

I'd like to know some details about this operation, like:

- how often this update happen?
- There is a particular job that make this?
- there is a way to force this update?
- there is a way to disable this update (besides confirm the production order)?

Thanks in advance.

Regards