Morning person for sure - I struggled to create this habit at the beginning, but now I am so grateful for it, just to be able to wake up at 5 AM and spend that time with myself: read, exercise, ride the bike is the best.
I am night person , I can concentrate more at night than in the morning as there are no disturbances around me. I used study at night in the morning and scored much more marks than when I studied in the day.
I'm not too sure, probably more of a night person.
In the mornings and when the sun's up is when I get a lot of my meetings and pings from colleagues so I find I end up doing nothing due to all the context switching. When night hits is when I finally have some time to crank out some actual work since I can focus undisturbed for the most part.