@ajewelinhiscrown Admittedly, I am not in your position (we decided to be 1 and done) so, I cannot truly understand dealing with that many kids at one time. Even so, when kiddo was younger, it was sometimes a struggle getting out the door on time (school is ~ 1km walking distance and we did not qualify for the bus even when kiddo was in kindergarten)... this is what I did to ensure that she got to school on time...
School-wear all laid out on the floor of the walk-in closet. Winter-wear or other stuff (need to take recyclable materials to the school next day, umbrella - check the weather the day before, etc.) kept by the door the night before. If it was possible to keep the lunch packed the previous night, I would do that (e.g. pasta salad can be packed the previous night, egg-wrap needs to be prepared fresh in the morning). Snacks are room-temp, so I could fill those in her box the previous night. Keep the water-bottle on the kitchen counter - along with the next morning breakfast's cutlery also kept ready there. The entire week's breakfast, lunch and snacks were decided on Friday evening of the week before (so that we could do grocery shopping on the weekend accordingly); these items were recorded in a table, so I did not have to think what had to be done the next day. Most breakfasts were a combination of banana, toast with butter, milk, nuts, boiled egg (boiled the previous night and kept ready) - so, little to no prep there.
The morning of school - all kiddo had to do was get up, washroom (before or after breakfast depending on when nature calls), eat breakfast, brush teeth, do hair, wear clothes and leave. When she was getting ready, I would make her lunch (if required - most times we had meal prep, so I did not have to make lunch in the morning), dump her stuff in her bag-pack and be ready to get out myself.
Edit: We have a strict bed-time - lights out at 8 p.m. for kiddo... even on the weekends... only exception is long holidays (that too, 3 nights before they end, we switch back to the early bed-time. Also, long holidays, bed-time is no later than 9 p.m.).