No BUMAT councelling hasn't been started yet. It is yet to be notified when will the process start. The entrance exam was conducted on 18th and 19th August and result was declared on 25th August. In councelling seats will be alloted to candidates based on the ranks secured by them and choice made by them while registering for the councelling.
Stay tuned to our website for BUMAT councelling dates. https://bschool.careers360.com/articles/bumat-counselling
Hope it helps.