Yes, we didn’t get into all the details to avoid unnecessary complexity, the truth is that expected averages can oscillate from 2400 to 2700 points per week, depending on the amount of Duel battles they play (from 0 to 3).
So anyway, the point of this line was mostly to provide a guide that highlights the weekly stabilisation and trends. There is a lot of noise in the data, so these variations shouldn’t make a big difference, but your observations are correct.