rolling, priority date admissions?

<p>hey i was applying to a few schools that have rolling admissions with really late deadlines but also offered these priority deadlines. How do rolling admissions really work? Do they look at students and give decisions first come first serve? or do they wait until the priority deadline and gather all the applications together and then make decisions? it would be great if anyone could help me. i'm really scared and confused because most of the schools i applied to have priority deadlines with rolling admissions. thanks!!</p>