Around workouts(before or during and then after) is a great time to do it.
Along with around times of sleep(before bed and as soon as you wake up).
During the day could be helpful too if you can afford it/don't mind cutting your supply short. But if you're eating properly you should be alright.
Also, if you know that you won't be able to eat for whatever reason, I would take some BCAAs so that you decrease catabolism!