Firstly, congratulations on successfully completing the VITEEE exam with flying colours. Getting CSE and IT seats is becoming really tough as they have high demand. Also, the cut-off trends is unpredictable and changes every year based on the number of students attempting the exam, difficulty level of the exam, number of seats available, etc. With a rank of 16000, you can secure a IT seat in Vellore campus in 2nd or 3rd category as the cut-off was 12000 in the year 2016 and 17000 in 2015. Just apply to their counselling process and get to know the exact category as its really hard to predict this year's cut-off.

https://engineering.careers360.com/articles/viteee-cutoff

You can have a look at the cut-off trends of the previous years from the above link.

Hope this helps!!

All the best for counselling process