Conversion of DTA units to EOU requires approvals, LUT execution, and transfer or preservation of advance and EPCG export obligations. Conversion of DTA units into EOUs requires approval from the Development Commissioner/Director, STPI, issuance of a Letter of Permission and execution of a Letter of Undertaking; thereafter the unit may obtain a private bonded warehousing licence and execute a B-17 bond. Raw materials under Advance Authorisation with valid export obligation periods may be carried forward to the EOU; outstanding EPCG obligations are absorbed into the EOU's future export obligation by adding the value of previously imported capital goods, after which prior EPCG obligations cease.