Dear Nuzhath, 

As you would know the All Indian Judiciary Exam is only an idea as of now and yet to realize in practicality. So far, for joining judiciary only State Judicial Service Exams are conducted by several states. If  you can tell which state's dates you are asking about, I will be able to tell you when it is likely to begin. 

You can find more information on the same in the article given below. 

State Judicial Service Examiantion – Overview and Preparation Tips

Hope it helps. 

All the best!