Hello, I would like to suggest you to keep the same branch in which you have completed your diploma. If you compare the syllabus of CS and IT the subjects are almost the same & there are no differences.

The subjects IT branch is having in it's second year, there might be a chance that CS branch having those subjects in third year syllabus. So if you see there is no difference between IT and CS. Only thing I'll suggest you is to keep your diploma and degree in same branch, do not change the branch. There are little chances of you might not feel that spark in your studies after changing the branch which was happened with me as well. So the answer to your question is CS or IT are not really different from each other, both are good and same if you want to pursue a carrer in any of these branches of engineering.

Thanks for reading.