I split mine (I only get two)...do half in the morning, then stick to water and coffee during the day.
If I'm doing two shakes in a day, I'll have a full one when I get home, then the other half later in the evening, otherwise if it's soup, i'll do the other half when I get home, then the soup later in the evening.
I think it's more of how you feel with it and as long as you get them in, as opposed to doing it at particular times.
I'm only a newbie to this, so maybe someone more "experienced" can clarify.