I prefer mornings for deep work because I find morning busy work will give me busy brain for the rest of the day. I often add in a tactic I heard from Josh Waitzkin, which is that you can prime your brain from the day before. End your day with a difficult challenge, let that unfinished work marinate in your head while you sleep, then begin your morning with journaling. Often my brain will have made weird connections overnight. And I feel more ready to jump into the flow.