Yes you are eligible to apply for MAH CET MBA exam even if you are in your final year. As officialy it states:

'Students, who are in the final year of their graduation, are also eligible to apply for MAH CET. However, in order to secure admission to an institute, they need to qualify the examination and also score as per the MAH CET cut off.'

So you can apply for the exam applications in the month of Jan 2018.