Hello Dave!
The Sibelius sound set triggers the "con fortissimo" type of the long notes. There is no command to trigger the "regular" type. With Dorico or Sibelius in most cases you shouldn't need the regular type, because you can trigger the lower velocity layers anyway with dynamic marks. "Con fortissimo" just means that a fortissimo layer is included for high velocities.
Best regards,
Andi
Vienna Symphonic Library