On finasteride switching to dutasteride

If you switch from fin to Dut, do you still have to wait ~12months to see progress?

Switching from finasteride to dutasteride just increases the effectiveness by 15% at most. Usually, you will see any benefits in about 3 months if you have been on finasteride for at least 6-9 months at the time of the switch. That is not saying that you will see any benefits regardless of how long you wait.