What is the best time to schedule junk collection?

We have 3 time slots, 9:30am – 2:00pm, 2:00pm-5:00pm, and 5:00pm-8:00pm.

Some security guards forbid the collection of junk after 5 PM. It is therefore better to be early in the morning, because if we are late, our truck might not have enough space for all the collected junk.