Extension of approval validity for SEZs requires Form C1 detailing implementation steps, justification, and commissioner recommendation. Form C1 is the prescribed application to extend formal approval validity for a Special Economic Zone under rule 6(2)(a). It requires developer identity, Letter of Approval details, SEZ type and sector, grant and expiry dates, whether notification and demarcation have occurred, a list of implementation steps undertaken, proposed completion timeframe, reasons for extension, an applicant declaration certifying truthfulness and acceptance of cancellation risk, applicant contact details, and the Development Commissioner's recommendation.