So Amazon was trying to make up for the delay/lateness by getting it to you as soon as they could.
Depends on the item, where it's available (how close to you), Prime membership, and so on.
I don't think they care about instructions, at least depending on what it's about. If the driver is working 4am to 8am and your instruction says no deliveries until after 10am, they will ignore it 'cause they get dinged for skipping a delivery. I do know for my account (our personal account), I order stuff for work and for our work address they know it's a business. With that, we can put in business hours and 90% of the time they follow those for deliveries. If I order something that will deliver at home on a weekend but I change the address to my work, it changes the next delivery to Monday.