Self-assessment procedure: revised RT-12 and PLA filing mandated; temporary stationery relaxation allowed; October defaults non penal. Notification No. 36/96-CE (NT) implements the self-assessment procedure, mandating revised RT-12, PLA and RG-23 return formats per Board Circular No. 249/83/96-CX. Triplicate copies are reallocated to the assessee and a temporary relaxation permits stamping existing triplicate/quadruplicate stationery as 'Triplicate for Assessee' until 31.3.97. Departments assessing October returns filed late should assess them and may request triplicate invoice copies; no penal action where October returns were not filed in the revised proforma.