Consent for authorised representative change required; Tribunal may permit substitution after revocation and service on record. A practitioner or authorised representative proposing to file a Vakalatnama, Memorandum of Appearance or letter of authorisation where another is on record must obtain the written consent of the practitioner or representative on record; if consent is refused, substitution requires Tribunal permission after revocation and service on the counsel already on record, except for applications falling within the specified statutory exception.