Lower branch in IIT or Cse in Thapar University?
However, I have seen people getting a good placement from Thapar in CS.
Check if you can get CS in some NITs? If yes, then you can plan to drop lower IITs for Top NITs. But if that is not the case then I would suggest you to try JEE next year, you will definitely get CS in goot IITs next year. This one year in preparation will be nothing as compared to your 35 years of working life.
IIT>>>>>>>THAPPAR