Arghya koner,

The validity of EWS certificates varies from one state to another. Most states have validity of one financial year ( 1st April to 31st March ). Recently rajasthan government has extended the ews certificate validity for 3 years. In west Bengal the validity of ews certificate is of 1 year only as I mentioned above. So to be eligible for admission under ews quota you must produce the valid ews certificate.

All the best :)