Peak is different.
Monday-Friday hubs run origin and destination relief sorts on added 6 day Sunday sorts to get ahead, and this makes advanced work available to the centers at the start of the week. During peak the hubs try to advance enough volume to balance the Monday-Tuesday dispatch in the local centers.
The centers themselves may even hold back available advanced work to avoid going too far and making Monday too much heavier than Tuesday, even with some centers taking advantage of a clause in some local supplements that allows a different start time for drivers for one day / week.
I was speaking more about the yearly - normal volume. What we do at peak changes things.