As it is only their first day with you, they have not had time to settle and show their "normal" patterns and you have not had the opportunity to spend time to get to know them. You have no basis on if there is any food aggression because they are pretty mixed up at this point.
Since you chose to leave pellets in the cage during the day (not really necessary, but some people do use a few in case of "midnight cravings") be sure to take those out before they wake up and toss them out so that they can be replaced with fresh ones the next day. You do not want them to fill up on something that has practically no nutritional benefit and then not being hungry enough to eat the good foods that you provide.
I rarely wait until they are awake unless I've gotten extremely distracted. My Maeve always wakes up a good half hour before her cage mates. So, even if I've forgotten, I hear her tip toeing around looking for the 'good stuff' before her friends wake up, and that prompts me to get their food in. On a usual night, you can set your clock to her being up at 8:45 (depending on time of year as well as other intermittent factors such as the weather, etc.)
Being that I'm able to predict fairly well that they won't be up earlier than 8:45, I have their food in at 8:15 which gives it time to thaw...and they have the comfort of knowing there is always fresh food to rely on.