I take 5 different tabs for different things and one is supposed to be in the morning. But I take mine all in the evening just before dinner and I get good blood test results.
I do it that way so it is easier to not forget, I leave all my tabs out where I can see them and take a handful before dinner. Easy Peasi!
Part of my handful is 5 Metformin slow acting. I believe (rightly or wrongly) that slow acting is not equal slow acting and it will have more effect when I first take it than when it is nearly due to be taken again.
I get good results so I have not considerd changing what I do.