If you go with the gamble and you are unable to meet the requirements to switch majors, you can change to another majot at UCI where you meet the requirements or have to transfer if you still want to pursue computer engineering. Being a dirct admit at CPP gives you the guarantee plus they do offer a 4 year pledge which if you follow the plan, will allow you to graduate in 4 years.
http://www.cpp.edu/~academic-programs/graduation-pledge/index.shtml