(8)Irrespective of anything contained in this section, where a partial partition has taken place after the foregoing provisions the of 31st December, 1978, among the members of a Hindu undivided family hitherto assessed as undivided,—(a)a claim that such partial partition has taken place shall not be inquired into under sub-section (2) and no finding shall be recorded under sub-section (3) that such partial partition had taken place and any finding recorded under sub-section (3) to that effect at any time, shall be null and void;(b)such family shall continue to be liable to be assessed under this Act as if no such partial partition had taken place; and(c)each member or group of members of such family immediately before such partial partition and the family shall be jointly and severally liable for any tax, penalty, interest, fine or other sum payable under this Act by the family in respect of any period, whether before or after such partial partition.