how to change the effectivity date of an activity operation?

We are creating the activities via the activity Workbench, copied from another Activity.

Then, the Effectivity Date of each operation, is given the actual date.

The problem is that usually we need to create a work order for the same day, so, the work order created (by the Forecast - Scheduling), gets no operation.

Is there a way to change the effectivity date of each operation after creating the Activity, or even at the moment of copying from another activity?

I am attaching some screens of this case.