GST Practitioner Examination requirement: mandatory certification introduced, with NACIN conduct, biannual tests and pass criteria enforced. Rule 83A mandates that enrolled GST practitioners must pass a NACIN conducted computer based multiple choice examination within a prescribed period, with NACIN setting schedules, registration, fees, centres, syllabus (Annexure A), fifty percent qualifying marks, no negative marking, rules on unfair means, disqualification, result declaration and representation procedures, and limited relaxation powers. Rule 142A requires uploading summaries of pre existing law demands to the common portal in FORM GST DRC 07A for recovery under GST and prescribes FORM GST DRC 08A for subsequent modification or rectification, with a substituted FORM GST PMT 01 ledger and related form amendments.