I mostly just add what I need to grind.
I can tell pretty well by eye how much to add to the hopper.
Occasionally though Ill try add enough to the hopper for maybe a few shots.
For example today Im using up the remainder of two commercial roasts Ive been drinking this past week.
One is a blend and the other is a SO Costa Rican.
Im pre-grind blending them in my hopper because I can and will finish them all today.
Although I generally keep my beans in the one-way valve bags until I need them, I dont see much difference coming from putting this lot all together in the hopper to use up today.
Someone with a 0480 will surely come along soon and give you any particular info pertaining to your Sunbeam.