Hello student,

You can definitely prepare for CAT very well while pursuing BBA, most people either prepare for CAT in the last year of their graduation or when they are working. Please do not make a mistake of dropping a year to prepare for CAT, it is an aptitude exam and it reflects badly in your interviews that you dropped a year just to prepare for CAT especially in top MBA college.

Only thing you must do is you just have to take out 3-4 hours from your daily routine. Actually CAT doesn't have syllabus related to management study they check your logical & verbal reasoning, data interpretation skills and English language skills. So any engineer or management student have equal chance to crack CAT. Take mock tests and assess yourself and review mocks seriously.

All the Best!!

Hello aspirant , it is good that you are planning ahead of time. Yes you can surely do that. You might face a little problem initially with accounts etc , but you will be able to cope with it. There would be student from commerce background , don't compare yourself with them . With hardwork you can beat them as well. 

PCM would give edge to MBA preoaration . You would not have problem in quant section. Moreover 3 years ( BBA duration ) is a good period of time to prepare for MBA . Your plan is absolutely okay..!!! Just go ahead with it..