Best time of day to do 1 Bottle feeding a day

I am going to cut my fawns down to 1 bottle feeding a day: Starting this weekend. Would like to hear some feed back on what time of day is best for 1 feeding a day. My 2 feedings time were 6:00 am and between 6-7 pm. Years ago when I bottle feed I did the 1 feeding at night. I was kinda watching to see witch feeding they would drink the most at but of course one time it would be the morning and then the next time it would be at night. So I am turning to all of you to help me out. What time do you do your 1 feeding a day? I allow my fawns to drink as much of Red Cap as they want. The fawns drink any were between 16 oz to 26 oz. at a feeding. When do you cut the red cap down to wean them or do you allow them to keep drinking all they want until just one day you don't bottle feed them. New with Red Cap first year for me.