I think you will find that the job ( RVBDEACT) looks at all activate batches, and will make a decision on whether the batch (currently active) is valid for deactivation i.e. if there is stock (or locked for inventory) you can't deactivate it, likewise if you perform a change to a deactivated batch then it will reactivate that batch again - thus a sensible approach to activating a deactivated batch.
Hope this helps.