SEZ unit approval: Letter of Approval governs commencement, extensions and licence status under SEZ rules. Application to set up a SEZ Unit is submitted to the Development Commissioner for transmission to the Approval Committee, which must decide within fifteen days. A Letter of Approval authorises the Unit but is time limited; the Unit must commence authorised activity within the Letter's validity or granted extensions or the Letter lapses. The Development Commissioner may grant extensions, including conditional extensions based on progress, and after commencement the Letter functions as a licence for authorised operations and may be extended further on request.