I am new to CVTs, I know how they work and mine has seven virtual computer generated gears. I can select them in "D" or "S" mode using the steering wheel gear selectors, providing that the computer is happy about appropriate speed etc. On my car the CVT will do a virtual downshift if you accelerate even slightly hard, the CVT instantly drops to an appropriate ratio. This may be the " jolt" you are feeling in "D" or "S" auto mode. I find for normal driving the CVT is best left to sort the ratio it requires, it is better than me at doing it and I have driven cars, HGVs, and Fire Engines for more years than I want to remember so I have a rough idea about gear selection. Has your car had the 25,000 mile CVT fluid change?