You could use VBA and set it up to link to an Option button on the worksheet. For instance, this code would allow you to change from monthly view to quarterly view of same data. You could add more lines to adjust the other pivot table, or you could have two option buttons one for each pivot table, and that way your double selection would be in one area.
Private Sub OptionButton1_Click()
' Months only
Application.ScreenUpdating = False
.PivotItems("Jan").Visible = True
.PivotItems("Feb").Visible = True
.PivotItems("Mar").Visible = True
.PivotItems("Q1").Visible = False
At least this might point you in the right direction.
old, slow, and confused
but at least I'm inconsistent!