Applied ED to Penn

When and how do the admissions officers read the applications? Do they wait until they have all the information about a student (SAT scores, all three recommendations, grades etc.) or do they start right away as soon as you submit your application on Nov 1st?

Penn’s website:
“The University of Pennsylvania reserves the right to evaluate an application and render a final decision even if all pieces of the application have not been received.”

In reality, I doubt they will review an application that is missing a major component of the application like SAT/ACT score. But at the same time, they have to go through thousands of applications in a month, so they’re not waiting forever. They’re certainly not waiting for your second recommendation letter to come in, let alone third.

I also doubt they start on 11/1. It takes some time to assemble 6K+ application packets.