For us there is a different Next Day Air Early AM truck. Aside from that, they don't leave the hub that early. They already get a bunch of overtime, our guy doesn't get back to the hub till 6 or later as it is at the end of the day. If he was out making 7:30am deliveries he would be putting in like a 12hr. day.
I suppose things are a bit different if you are maybe in a smaller area then we are(1hub 20min south of us and another 20min west of us) with less trucks, but I still can't imagine UPS scheduling their drivers for a standard 12hr. day.
You should ask your driver what time he usually leaves the hub. I wouldn't bring up your current issue, make it more of a shooting the breeze conversation... It's too bad because the likelihood of actually getting a straight honest answer from UPS(not the actual driver, I consider them entity) about the early am delivery is pretty much 0%. Word to the wise- a nice $20 or a crisp $50, even the offer of spot inside in some AC where he is always welcome to eat his lunch, to the driver in your busy season while it is HOT out goes a LONG way! We have also found a popsicle or treat from Dairy Queen also works well;D