There is no such specific date mentioned yet. However, it is said that the counselling will be starting this month. Qualified candidates will be eligible to participate in the counseling of IMU CET 2021. It is necessary for all candidates to be registered for the counselling session within the duration notified by the authorities. During the counselling, you will be allotted to the campuses of Indian Maritime University. The counselling of IMU CET 2021 is held only for the campuses.
Stay in touch with this website for further updates- https://engineering.careers360.com/articles/imu-cet-counselling
Hope this helps!
According to my information the counselling starting date is not announced yet.