I know, it irritates the h*l* out of me.
Mid-morning - 10
First thing in the morning - 7
Lunch time - 12
Early afternoon - 1
Mid-afternoon - 3
Late afternoon - 4
Early evening - 5
Supper time - 6
The end of the week - Sat
The first of the month - 1st
I always try to K.I.S.S.