If you applied to Smeal and are denied a spot in the school, will they still offer you admission to the main campus or will you be denied altogether? Personally, I would still go to Penn State if I didn’t get accepted to Smeal so it worries me that I can be completely denied.
You’d be denied and have to call Admissions within 24h and ask to be considered for DUS.
If there’s even a doubt (ie’, you don’t have 1450+/3.8+), call now and all to be switched to DUS to save yourself the time and anxiety. There’s no difference between DUS and Smeal for the first two years - you take the same classes, have the same date of registration, the same premajor requirements, etc.