law: 11. Limitation for applications for fixation of standard rent.-
  Any landlord or tenant may file an application to the court for fixing the standard rent of the premises or for determining the lawful increase of such rent-
  (a) in the case of any premises which were let, or in which the cause of action for lawful increase of rent arose, before the commencement of this Act, within six months from such commencement;
  (b) in the case of any premises let after the commencement of this Act, within six months from the date on which it is so let; and
  (c) in the case of any premises in which the cause of action for lawful increase of rent arises after the commencement of this Act, within six months from that date: Provided that the court may entertain the application after the expiry of the said period of six months if it is satisfied that the applicant was prevented by sufficient cause from filing the application in time.