if you are going to switch then you ideally need to run the tank near empty say with 5 or 0 miles left on the trip comp otherwise the higher ron rating fuel will become diluted, and as mentioned it will take time for the ECU to register the higher quality fuel and adjust timing, fueling and boost to compensate. If you read the information carefully, the engine only kicks out 200ps on 99 ron fuel anything else will cause knocking and the engine will have to pull back to bring the combustion cycle within spec.