When I was on 4, I started taking them all in once, mornings. But since I'm no-breakfast-at-all person, those 4 pills made my guts filling not so fine. So I split them, took 2 in the mornings and 2 around 4-5 pm. It worked just well for me.
Now I'm on 3 pills a day, taking them all in the morning but probably will split those as well.
According to my GI, one should be fine taking all 4 in the morning... but that's just 'according to my GI' sort of thinking
PS. oh, well, I need to change my signature