Use the Jeppesen speed/MDA chart
I think your question is must you use the higher minimum if the higher airspeed is used only before maneuvering.
When you begin an approach and plan to circle, I believe that you use circling minima. If you are at 140 kts, yet fly to the MDA for 120 kts, that seems to be contrary to the Jepp published minima. In fact, this would be contrary to what many operators are doing these days. That is, many have the pilot fly to the highest minima published for the circling approach. The reason for this is because otherwise a circling approach delivers the aircraft to low speed maneuvering at low altitude, in poor visibility at a time of high cockpit workload. At this point your company wants you to configure and change airspeed while maintaining visual with the runway?