Ya I see your point. The work around I have for that only works vertically but I put 2 of the same properties in the row grouping and one is by Month & one is by Week. Then we just display 1 at a time to view by month or week.
But it would be alot cleaner if we could do that on the columns. It should be a toggle here where you select the Time Interval, but on the column lol.
Also by grouping by Qrt would be nice.