Hii

Appearing for april session exam is your own choice it is not compulsory. The best of the two scores will be consdered for the further processes. So it completely depends on you whether you wish to appear for april exam or not.
The final result will be declared after april exam only, so as of now the exact rank can not be predicted.
But expected rank can be calculated with the following formula
100- your score * total students appeared / 100
Where the total students are 874469.
For 96.11 percentile, you expected rank would be 34016.

Hope this helps

Thanks!!