I find that problem when the pumps have the new nozzle, that prevents topping off the tank, when it does work and kicks off it makes it hard to round off.
I've pieced together a dedicated run 2 pick up and 5 drops, 210 miles 5 days a week leave my house at 9:30 am home by 4:30 pm pays $195.00 a day, so it can be done if you plan your work and work your plan