It occurs right before the shift. You feel a hard pull back right before it shifts
It feels like the car has lost power but then it shifts and starts to accelerate again. If you are using it with the paddle shifters you can tell a second or two goes by between the time you clicked the paddle and it switching gears. None of the other gear shifts do this.
That doesnt sound normal. It should be smooth.
I would find another dealership or continue to push your dealership that this is an issue.