<p>You r accepted to the College of Engineering. You start taking ur major specific classes like 2-4 semesters in. You van declare whenever u want. It really doesn’t matter. You don’t have to be declared to a program to take its classes (except for some 400 level courses). </p>
<p>I’ll be declaring sometime my second year. I assume that’s when most do. </p>
<p>As for moving from program to program, again if you aren’t declared u r just taking certain courses required by that program. So it would b as easy as just scheduling different courses.</p>