Hello aspirant

2019 cut off for pwd category student was 0.11371730 ( all India  rank) . Cut off depends on number of candidates appeared and qualified, difficulty level of exam, previous year's cut off. So this year it may increase.

Your all India rank with 39.6393106 percentile will be around 524,540 .

So you have good chance for a seat in nit being from SC -PWD .

For more information you can follow the link given below

https://engineering.careers360.com/jee-main-college-predictor