In principle, that could create a new peak period. Reducing the demand for electricity at certain times during the day could increase consumption at other times. This phenomenon is known as load pickup and Hydro-Québec monitors it closely.
To create a peak, the entire population would have to do the same thing at the same time. In reality, the probability of creating a new peak period is low since there are so many different uses and Québec households have different habits.