(c)who has become an insolvent, shall be qualified to represent any person under sub-section (1), for all times in the case of a person referred to in clause (a), and for such time as the Collector or Central Excise or of Customs or the competent authority under the Customs Act, 1962 (52 of 1962) or the Central Excises and Salt Act, 1944 (1 of 1944) as the case may be, may, by order, determine in the case of a person referred to in clause (b), and for the period during which the insolvency continues in the case of a person referred to in clause (c).