Deepak there is no exact time deadline mentioned on the official website. It is only mentioned that candidates can upload their corrected category certificates on or before 5th June 2018. So, this means the portal might be closing at the end of the day i.e. 12'o clock in the night but still it's just an assumption and that portal can even close in the evening 5 or 6 o'clock which is the official closing time of working hours. Hence I strongly advise being on the safe side you to finish up your document uploading work before tomorrow's evening and save yourself from any further problem.

Feel free to ask if you have any more queries. All the best!!