That was Method #1
I am sure you are aware that in about 6 sec after you downshifted it will revert to full AutoPDK...
Method #2 (not recommended to use in the twisties, until you are thoroughly familiar with the PDK behavior).
Instead of using the left paddle to downshift, you punch the gas pedal.
Here comes the hard part:
Depending on how 'deep' the punch was, and how short in time, one of the following will happen:
1) Too shallow and short punch (you have to figure out what this means): The car will accelerate, possibly anemically, since it is in low revs for the downshift.
2) Just the right depth and duration punch: The car will downshift one gear and stay in automatic.
3) Sublimely correct punch: The car will downshift two gears and you wanted to downshift two gears, and stay in automatic
4) Floor and hold the gas pedal: All **** breaks loose, the car will downshift as many gears as it can, taking the engine to or near the red line
Fun!