(i) no appointment of any person already in the judicial service of a State or of any person who has been for not less than seven years an advocate or a pleader, to be a district judge in that State, and

no posting, promotion or transfer of any such person as a district judge,

no jurisdiction exercised, no judgment, decree, sentence or order passed or made, and no other act or proceeding done or taken, before the commencement of the Constitution (Twentieth Amendment) Act, 1966 by, or before, any person appointed, posted, promoted or transferred as a district judge in any State otherwise than in accordance with the provisions of article 233 or article 235 shall be deemed to be illegal or invalid or ever to have become illegal or invalid by reason only of the fact that such appointment, posting, promotion or transfer was not made in accordance with the said provisions.