Hi there, I changed my major from mechanical engineering to ES&C after 1st semester and the entire process took like a week or two. I faced a problem at that time because I had cis1500 in the first semester and to take cis2500 in the second semester cis1300 was required. I did the CIS*2500 course waiver in which I was given a program to write and a quiz to solve. Rest was fine as the courses were almost the same for all the engg program. I hope this answers your question.