When are the admissions decisions for early round applications actually made? The letters/emails are usually sent mid-December, so has the college been doing some sort of post-processing for a while before sending decisions out, or are they still deciding right up to the release date? This is mostly about the bulk of applicants, since there’s probably always going to be at least some applications that take a little longer to decide on.
Each place has its own system. If you want to know about a particular institution’s process, you need to ask them.
This is the kind of thing that consumes you when you are applying to college.
With time, you will realize that you will be given a decision around the date that they say they will notify you and the inner workings are not important.
If you want to share something with admissions (significant award, etc) go ahead. It will help or it won’t.