Staggering hatches means that you put the eggs in on different days so they hatch out at different times. A lot of people do this if they have a hatcher (or a second bator they use as a hatcher). I'm doing this now as I have one group of eggs that will be ready to move into my second bator for hatching on Wednesday, and a second batch that has only been in the bator for a few days. When my quail eggs arrive I'll be adding them to the bator, and then I'll move the chicken eggs out to the 'hatcher' when they are ready.
Well, you have a 2nd bator, that's better than I did. Just make sure you write the date on the big end of the egg, so you can see which are which. Also, try to seperate them by a week to make room for early and late hatchers, so you'll have time in between to clean the hatcher.