My writing routine has settled to the evenings over the past few years. Before that I used to write in the morning, mostly as I was commuting and it was a good time to write. I still do write in the morning if I'm going to the office, but that doesn't happen too often anymore. Just the old habit kicking in.
A third option I have used, mostly when I know the evening will be busy and I might not have a chance to write, is to write in the afternoon. There hasn't been too many such occasions especially as many times in those situations I have written in the morning instead.
Besides those three times I don't think I habe written much of any other times. There might have been some odd days when it has happened, but I can't remember any. So this might very well be the first time in almost six years when I'm writing at my lunch break.