Welcome to Brown Cafe CardsFan.
Hopefully you will get a few pertinent answers here.
This site has a lot of drivers and as you can see from their replies, they think the UPS world revolves around them.
You have to hit them upside the head with a virtual sledgehammer to make them realize there is a world outside of package pickup and delivery.
Seriously though, you have to spell it out very demonstrably that you are looking for hub sort start times.
Good luck!