Using ASCP and BOM to plan items.

Hi

We have the following scenario and I am not sure how to approach the following scenario.

Our customer orders consists of multiple packages that should be distributed on various dates to the customer.

These date are managed by the BOM. 

The first package is sent to the customer as soon as the items are active on the BOM for a specific year.

As the rest of the items are "activated" on the BOM a custom program adds these lines to a SO.

My question is the following.

In order to create a Planned Order through ASCP for these items, my understanding is that the forecast date can only be once all the items are active on the BOM. Otherwise ASCP will not create a Planned Order for these item.