Dropping a year is a very risky decision and has its own consequences. So it’s better you analyze your prospects and inclinations before forgoing an offer from any IIM be it Bodh Gaya or Sambalpur. It requires a lot of courage to risk an entire year just to target a better B School. Sometimes it’s worth it and sometimes it’s not. So I will suggest you to forgo such an offer only if

• You have a perfect plan to prepare excellently for CAT next year and you are confident you will score a higher percentile 
• You are good at the DILR section. Even if you prepare for your CAT again, you cannot improve much in the DILR section. You can improve your quantum and verbal skills but not much in the DILR section. So if that is one of your weaknesses, I don’t think leaving the offer is worth the risk.
• You are going to work somewhere and gain experience. This is very crucial as during the interview you cannot say you took a drop year merely because you wanted to prepare for CAT.

I will say that IIM Bodh Gaya is not bad of a choice mainly because it is an IIM under the mentorship of IIM Calcutta.

My cousin faced a similar dilemma. Initially, she was stuck and could not decide which college to go to. Ultimately she made a decision after analyzing the pros and cons of both institutions. She told me that one has to be extremely sure about what one wants to pursue in order to make this decision.

You should go for any of both the IIMs if

• If you value the IIM tag more than anything even the course itself
• If you are looking for great exposure to your life and want overall development rather than just Master

You may go for Christ University if 

• If you want to just pursue BBA and gain a job experience 
• If you are not willing to spend a rendezvous fee at IIMs

One major advantage of going for IPM from any IIM is that they all offer an exit option after 3 years, so if you give CAT and you are unable to get enough score to get shortlisted by any IIM, then you are on the safer side. This is because you will have an MBA degree and that too from one of the most reputed B schools in the nation. Whereas this may not be possible if you go for BBA.

People might be concerned that both these IIMs are comparatively new. But depending on the predictions these are bound to flourish in the years to come.

The final decision is based on your own convenience and interests.